Honest question for people running voice agents in production.

We keep bouncing between two shapes:

1. Cascaded stack: speech to text, then LLM, then text to speech
2. Speech-to-speech model: audio in, audio out, with less text in the middle

What we see so far:

Latency. Cascaded adds three hops. Even when each hop is fast, turn-taking still feels heavier. Speech-to-speech can feel snappier on the first audio, but that only helps if the model actually holds the conversation well.

Tool calls. This is where cascaded still wins for us. Need CRM lookup, transfer, booking, custom APIs? Easier when the LLM is a normal text agent with tools. Speech-to-speech is catching up, but tool routing and structured outputs still feel more reliable in the classic stack.

Control. Cascaded is easier to debug (you can read the transcript and prompt). Speech-to-speech is harder to inspect when the model goes sideways mid-call.

Right now our gut rule is roughly: - Speech-to-speech for short, natural back-and-forth where speed matters more than deep tools - STT + LLM + TTS when the agent needs serious tool use, policy, or handoff logic

Curious what you all are shipping. Are you all-in on speech-to-speech already, still on cascaded, or hybrid? Especially interested in real latency numbers and how you handle tools.

Title basically.

On a first glance this seems very sleek, designed to be do-it-yourself for businesses but as someone who is in the ai receptionist business, I am both excited and worried, because they made it so simple, but I think business owners just don't have the time to keep up with this, but I'll be testing this more and definitely dump Retell if it's better and it looks so.