Synchronize video/audio directly in Finder. Just select some video files + high quality audio file , right click , Synchronize , and get a file with replaced audio. No long rendering, results in secs.
To install this Finder extension, download the DMG, move to Apps folder. Run the app once. Quit it(from top left file Menu) , run it again.Then check in Extensions Prefs whether this extension is enabled. From then onwards, you are ready to use it.