I tested most of the AI lipsync tools via API, most are not production-usable / Notes from 2 weeks of pain

I have spent 2 weeks feeding the same 30-sec clip + an ElevenLabs Spanish track through everything I could get an API for. Honest, because the marketing pages all say photorealistic and most aren't.

What broke most of them:
1/ Obstructions - the second a hand or mic crosses the mouth, most tools smear the whole lower face. Only a couple handled it.
2/ Teeth - cheap tools turn teeth into a white blur on close-ups. Instant "this is AI" tell.
3/ Multiple speakers - anything with two people talking, most tools sync the wrong mouth.

Roughly how they landed for me:
1/ Wav2Lip - free/open source, but low-res and mushy above a headshot, plus Colab babysitting.
2/ HeyGen - polished, but on my own real footage the sync was weaker than dedicated tools.

3/ Sync (sync.so) - held up on close-ups (teeth stayed intact on lipsync-2-pro) and survived an obstruction take. Not flawless, fast head-turns still wobble a bit and I cut around them, but it was the only one I'd hand a client.

If your use case is ‘sync my client’s real footage to new audio,’ the field is way thinner than the tool count suggests.