diff --git a/docs/storage.md b/docs/storage.md
index 55f8d01..3eeff55 100644
--- a/docs/storage.md
+++ b/docs/storage.md
@@ -90,14 +90,14 @@ getDownloadURL(davidRef)
 ```
 
 ### `getMetadata()`
-The `getMetadata()` function creates an observable that emits the URL of the file's metadta.
+The `getMetadata()` function creates an observable that emits the full set of object metadata, including read-only properties..
 
 |                 |                                          |
 |-----------------|------------------------------------------|
 | **function**    | `getMetadata()`                          |
 | **params**      | `import('firebase/storage').StorageReference`                      |
 | **import path** | `rxfire/storage`                         |
-| **return**      | `Observable<Object>`                     |
+| **return**      | `Observable<FullMetadata>`                     |
 
 #### TypeScript Example
 ```ts
diff --git a/firestore/collection/index.ts b/firestore/collection/index.ts
index 1a2ae88..ef0a1a2 100644
--- a/firestore/collection/index.ts
+++ b/firestore/collection/index.ts
@@ -33,9 +33,8 @@ import {
   pairwise,
 } from 'rxjs/operators';
 import {snapToData} from '../document';
-import {DocumentChangeType, DocumentChange, Query, QueryDocumentSnapshot, QuerySnapshot, DocumentData} from '../interfaces';
+import {DocumentChangeType, DocumentChange, Query, QueryDocumentSnapshot, QuerySnapshot, DocumentData, CountSnapshot} from '../interfaces';
 import {SnapshotOptions, getCountFromServer, refEqual} from 'firebase/firestore';
-import {CountSnapshot} from '../lite/interfaces';
 const ALL_EVENTS: DocumentChangeType[] = ['added', 'modified', 'removed'];
 
 /**
@@ -298,10 +297,14 @@ export function collectionData<T=DocumentData, U extends string=never>(
   );
 }
 
-export function collectionCountSnap(query: Query<unknown>): Observable<CountSnapshot> {
+export function collectionCountSnap<AppModelType = DocumentData>(
+    query: Query<AppModelType>,
+): Observable<CountSnapshot<AppModelType>> {
   return from(getCountFromServer(query));
 }
 
-export function collectionCount(query: Query<unknown>): Observable<number> {
+export function collectionCount<AppModelType = DocumentData>(
+    query: Query<AppModelType>,
+): Observable<number> {
   return collectionCountSnap(query).pipe(map((snap) => snap.data().count));
 }
diff --git a/firestore/document/index.ts b/firestore/document/index.ts
index 0025501..f42efb0 100644
--- a/firestore/document/index.ts
+++ b/firestore/document/index.ts
@@ -54,8 +54,8 @@ export function snapToData<T=DocumentData, R extends T=T>(
     return data;
   }
 
-  return {
-    ...data,
-    [options.idField]: snapshot.id,
-  };
+  // Preserve converter instances and custom prototypes by mutating the original object
+  // instead of creating a new one with spread syntax.
+  Object.assign(data, {[options.idField]: snapshot.id});
+  return data;
 }
diff --git a/firestore/interfaces.ts b/firestore/interfaces.ts
index 0341fad..9dfea0a 100644
--- a/firestore/interfaces.ts
+++ b/firestore/interfaces.ts
@@ -7,3 +7,11 @@ export type QuerySnapshot<T> = import('firebase/firestore').QuerySnapshot<T>;
 export type DocumentChangeType = import('firebase/firestore').DocumentChangeType;
 export type DocumentChange<T> = import('firebase/firestore').DocumentChange<T>;
 export type QueryDocumentSnapshot<T> = import('firebase/firestore').QueryDocumentSnapshot<T>;
+export type CountSnapshot<
+  AppModelType = DocumentData,
+  DbModelType extends DocumentData = DocumentData,
+> = import('firebase/firestore').AggregateQuerySnapshot<
+  {count: import('firebase/firestore').AggregateField<number>},
+  AppModelType,
+  DbModelType
+>;
diff --git a/firestore/lite/collection/index.ts b/firestore/lite/collection/index.ts
index 2bab09c..412d1d6 100644
--- a/firestore/lite/collection/index.ts
+++ b/firestore/lite/collection/index.ts
@@ -35,10 +35,10 @@ export function collection<T=DocumentData>(query: Query<T>): Observable<QueryDoc
  * Returns a stream of documents mapped to their data payload, and optionally the document ID
  * @param query
  */
-export function collectionData<T=DocumentData>(
+export function collectionData<T=DocumentData, R extends T=T>(
     query: Query<T>,
     options: {
-    idField?: string
+    idField?: keyof R
   }={},
 ): Observable<T[]> {
   return collection(query).pipe(
@@ -48,10 +48,18 @@ export function collectionData<T=DocumentData>(
   );
 }
 
-export function collectionCountSnap(query: Query<unknown>): Observable<CountSnapshot> {
+export function collectionCountSnap<
+  AppModelType = DocumentData,
+  // DbModelType extends DocumentData = DocumentData,
+>(query: Query<AppModelType>): Observable<CountSnapshot<AppModelType>> {
   return from(getCount(query));
 }
 
-export function collectionCount(query: Query<unknown>): Observable<number> {
+export function collectionCount<
+  AppModelType = DocumentData,
+  // DbModelType extends DocumentData = DocumentData
+>(
+    query: Query<AppModelType>,
+): Observable<number> {
   return collectionCountSnap(query).pipe(map((snap) => snap.data().count));
 }
diff --git a/firestore/lite/document/index.ts b/firestore/lite/document/index.ts
index 6fd8849..f126ad3 100644
--- a/firestore/lite/document/index.ts
+++ b/firestore/lite/document/index.ts
@@ -29,30 +29,30 @@ export function doc<T=DocumentData>(ref: DocumentReference<T>): Observable<Docum
  * Returns a stream of a document, mapped to its data payload and optionally the document ID
  * @param query
  */
-export function docData<T=DocumentData>(
+export function docData<T=DocumentData, R extends T=T>(
     ref: DocumentReference<T>,
     options: {
-    idField?: string
+    idField?: keyof R,
   }={},
-): Observable<T> {
+): Observable<T | R | undefined> {
   return doc(ref).pipe(map((snap) => snapToData(snap, options) as T));
 }
 
-export function snapToData<T=DocumentData>(
+export function snapToData<T=DocumentData, R extends T=T>(
     snapshot: DocumentSnapshot<T>,
     options: {
-      idField?: string,
+      idField?: keyof R,
     }={},
-): {} | undefined {
-  // TODO clean up the typings
-  const data = snapshot.data() as any;
+): T | R | undefined {
+  const data = snapshot.data();
   // match the behavior of the JS SDK when the snapshot doesn't exist
   // it's possible with data converters too that the user didn't return an object
-  if (!snapshot.exists() || typeof data !== 'object' || data === null) {
+  if (!snapshot.exists() || typeof data !== 'object' || data === null || !options.idField) {
     return data;
   }
-  if (options.idField) {
-    data[options.idField] = snapshot.id;
-  }
+
+  // Preserve converter instances and custom prototypes by mutating the original object
+  // instead of creating a new one with spread syntax.
+  Object.assign(data, {[options.idField]: snapshot.id});
   return data;
 }
diff --git a/firestore/lite/interfaces.ts b/firestore/lite/interfaces.ts
index a9ba75c..d4d64e2 100644
--- a/firestore/lite/interfaces.ts
+++ b/firestore/lite/interfaces.ts
@@ -2,10 +2,17 @@ import type * as lite from 'firebase/firestore/lite';
 
 export type DocumentReference<T> = lite.DocumentReference<T>;
 export type DocumentData = lite.DocumentData;
-export type Query<T> = lite.Query<T>;
+export type Query<AppModelType> = lite.Query<AppModelType>;
 export type DocumentSnapshot<T> = lite.DocumentSnapshot<T>;
 export type QuerySnapshot<T> = lite.QuerySnapshot<T>;
 export type QueryDocumentSnapshot<T> = lite.QueryDocumentSnapshot<T>;
-export type CountSnapshot = lite.AggregateQuerySnapshot<{
-  count: lite.AggregateField<number>;
-}, any, DocumentData>;
+export type CountSnapshot<
+  AppModelType = DocumentData,
+  DbModelType extends DocumentData = DocumentData,
+> = lite.AggregateQuerySnapshot<
+  {
+    count: lite.AggregateField<number>;
+  },
+  AppModelType,
+  DbModelType
+>;
diff --git a/performance/index.ts b/performance/index.ts
index 0e05cd2..fa5b34b 100644
--- a/performance/index.ts
+++ b/performance/index.ts
@@ -50,12 +50,10 @@ const trace$ = (traceId: string) => {
 export const trace = <T = any>(name: string) => (source$: Observable<T>) => new Observable<T>((subscriber) => {
   const traceSubscription = trace$(name).subscribe();
   return source$.pipe(
-      tap(
-          () => traceSubscription.unsubscribe(),
-          () => {
-          },
-          () => traceSubscription.unsubscribe(),
-      ),
+      tap({
+        next: () => traceSubscription.unsubscribe(),
+        complete: () => traceSubscription.unsubscribe(),
+      }),
   ).subscribe(subscriber);
 });
 
@@ -73,14 +71,16 @@ export const traceUntil = <T = any>(
   options?: { orComplete?: boolean },
 ) => (source$: Observable<T>) => new Observable<T>((subscriber) => {
   const traceSubscription = trace$(name).subscribe();
-  return source$.pipe(
-      tap(
-          (a) => test(a) && traceSubscription.unsubscribe(),
-          () => {
-          },
-          () => options && options.orComplete && traceSubscription.unsubscribe(),
-      ),
-  ).subscribe(subscriber);
+  return source$
+      .pipe(
+          tap({
+            next: (value) => test(value) && traceSubscription.unsubscribe(),
+            complete: () =>
+              options &&
+          options.orComplete &&
+          traceSubscription.unsubscribe(),
+          }),
+      ).subscribe(subscriber);
 });
 
 /**
@@ -98,23 +98,27 @@ export const traceWhile = <T = any>(
   options?: { orComplete?: boolean },
 ) => (source$: Observable<T>) => new Observable<T>((subscriber) => {
   let traceSubscription: Subscription | undefined;
-  return source$.pipe(
-      tap(
-          (a) => {
-            if (test(a)) {
-              traceSubscription = traceSubscription || trace$(name).subscribe();
-            } else {
-              if (traceSubscription) {
-                traceSubscription.unsubscribe();
+  return source$
+      .pipe(
+          tap({
+            next: (value) => {
+              if (test(value)) {
+                traceSubscription =
+              traceSubscription || trace$(name).subscribe();
+              } else {
+                if (traceSubscription) {
+                  traceSubscription.unsubscribe();
+                }
+                traceSubscription = undefined;
               }
-              traceSubscription = undefined;
-            }
-          },
-          () => {
-          },
-          () => options && options.orComplete && traceSubscription && traceSubscription.unsubscribe(),
-      ),
-  ).subscribe(subscriber);
+            },
+            complete: () =>
+              options &&
+          options.orComplete &&
+          traceSubscription &&
+          traceSubscription.unsubscribe(),
+          }),
+      ).subscribe(subscriber);
 });
 
 /**
@@ -126,13 +130,9 @@ export const traceWhile = <T = any>(
 export const traceUntilComplete = <T = any>(name: string) => (source$: Observable<T>) => new Observable<T>((subscriber) => {
   const traceSubscription = trace$(name).subscribe();
   return source$.pipe(
-      tap(
-          () => {
-          },
-          () => {
-          },
-          () => traceSubscription.unsubscribe(),
-      ),
+      tap({
+        complete: () => traceSubscription.unsubscribe(),
+      }),
   ).subscribe(subscriber);
 });
 
@@ -145,12 +145,8 @@ export const traceUntilComplete = <T = any>(name: string) => (source$: Observabl
 export const traceUntilFirst = <T = any>(name: string) => (source$: Observable<T>) => new Observable<T>((subscriber) => {
   const traceSubscription = trace$(name).subscribe();
   return source$.pipe(
-      tap(
-          () => traceSubscription.unsubscribe(),
-          () => {
-          },
-          () => {
-          },
-      ),
+      tap({
+        next: () => traceSubscription.unsubscribe(),
+      }),
   ).subscribe(subscriber);
 });
diff --git a/storage/index.ts b/storage/index.ts
index 9dad2d8..6b6c085 100644
--- a/storage/index.ts
+++ b/storage/index.ts
@@ -7,14 +7,23 @@ import {
 import {Observable, from} from 'rxjs';
 import {map, shareReplay} from 'rxjs/operators';
 
-import type {UploadTaskSnapshot, StorageReference, UploadMetadata, StringFormat, UploadTask, UploadResult} from 'firebase/storage';
+import type {
+  UploadTaskSnapshot,
+  StorageReference,
+  UploadMetadata,
+  StringFormat,
+  UploadTask,
+  UploadResult,
+  FullMetadata,
+  StorageError,
+} from 'firebase/storage';
 
 export function fromTask(task: UploadTask): Observable<UploadTaskSnapshot> {
   return new Observable<UploadTaskSnapshot>((subscriber) => {
     let lastSnapshot: UploadTaskSnapshot | null = null;
     let complete = false;
     let hasError = false;
-    let error: any = null;
+    let error: StorageError | null = null;
 
     const emit = (snapshot: UploadTaskSnapshot) => {
       lastSnapshot = snapshot;
@@ -74,9 +83,13 @@ export function getDownloadURL(ref: StorageReference): Observable<string> {
   return from(_getDownloadURL(ref));
 }
 
-// TODO: fix storage typing in firebase, then apply the same fix here
-// eslint-disable-next-line @typescript-eslint/no-explicit-any
-export function getMetadata(ref: StorageReference): Observable<any> {
+/**
+ * Retrieves the metadata for a given storage reference.
+ *
+ * @param ref The storage reference for which to retrieve metadata.
+ * @returns An observable that emits the metadata for the given reference.
+ */
+export function getMetadata(ref: StorageReference): Observable<FullMetadata> {
   return from(_getMetadata(ref));
 }
 
diff --git a/test/firestore-lite.test.ts b/test/firestore-lite.test.ts
index 18ff4cb..bd0d561 100644
--- a/test/firestore-lite.test.ts
+++ b/test/firestore-lite.test.ts
@@ -214,6 +214,28 @@ describe('RxFire firestore/lite', () => {
         });
       });
     });
+
+    it('docData should preserve converter instances when idField is set', (done: jest.DoneCallback) => {
+      class Folk {
+        constructor(public name: string) {}
+        static fromFirestore(snap: QueryDocumentSnapshot) {
+          return new Folk(snap.data().name);
+        }
+        static toFirestore(model: Folk) {
+          return model;
+        }
+      }
+
+      seedTest(firestore).then(({davidDoc}) => {
+        const unwrapped = docData<Folk, Folk & {UID: string}>(davidDoc.withConverter(Folk), {idField: 'UID'});
+
+        unwrapped.pipe(take(1)).subscribe((val) => {
+          expect(val).toBeInstanceOf(Folk);
+          expect(val).toEqual(expect.objectContaining({name: 'David', UID: 'david'}));
+          done();
+        });
+      });
+    });
   });
 
   describe('Aggregations', () => {
diff --git a/test/firestore.test.ts b/test/firestore.test.ts
index 0274c3a..b65f18a 100644
--- a/test/firestore.test.ts
+++ b/test/firestore.test.ts
@@ -416,6 +416,28 @@ describe('RxFire Firestore', () => {
       });
     });
 
+    it('docData should preserve converter instances when idField is set', (done: jest.DoneCallback) => {
+      class Folk {
+        constructor(public name: string) {}
+        static fromFirestore(snap: QueryDocumentSnapshot) {
+          return new Folk(snap.data().name);
+        }
+        static toFirestore(model: Folk) {
+          return model;
+        }
+      }
+
+      seedTest(firestore).then(({davidDoc}) => {
+        const unwrapped = docData<Folk, Folk & {UID: string}>(davidDoc.withConverter(Folk), {idField: 'UID'});
+
+        unwrapped.pipe(take(1)).subscribe((val) => {
+          expect(val).toBeInstanceOf(Folk);
+          expect(val).toEqual(expect.objectContaining({name: 'David', UID: 'david'}));
+          done();
+        });
+      });
+    });
+
     /**
      * TODO(jamesdaniels)
      * Having trouble gettings these test green with the emulators