Yes, Sonic 3.5 looks really solid so far much more natural pacing, cleaner audio, and better handling of numbers/emails compared to Sonic 3. And yes, you should be able to use it with Vapi via the Cartesia provider, although support may still depend on whether Vapi has exposed the new sonic-3.5 model ID in their dashboard/API yet. Vapi already supports Cartesia Sonic models. I can help you test/configure it inside Vapi if you want. @eatdogs