I use Gemini via its web app, which aggressively autoswitches to the Flash over Pro, but I usually notice quickly because the answers are weird or the logic doesn't quite follow. I feel like, at least for 'daily driver' usage, small models are still a little disappointing. That said, they're getting very good for more automation-y tasks with simple, well-constrained tasks.
I got Codex to whip me up a Chrome extension that autoswaps back to Pro whenever I reload the page. It's made Gemini significantly less irritating to use.