I'm a big user of Gemini voice. My sense is that Gemini voice uses very tight system prompts that are designed to give you an answer and kind of get you off the phone as much as possible. It doesn't have large context at all.

That's how I judge quality at least. The quality of the actual voice is roughly the same as ChatGPT, but I notice Gemini will try to match your pitch and tone and way of speaking.

Edit: But it looks like Gemini Voice has been replaced with voice transcription in the mobile app? That was sudden.