In my experience starting with Gemini 2.5 Pro, moving to 3 and 3.1, 3.5 Flash, 3.6 Flash, and finally 3.7 Flash, 3.7 Flash is just as good if not better than 3 especially on high resolution mode (same token count per page as 3.1).

I run complicated, messy PDFs through these models. 2.5 Pro required a lot of kludgy hacks to get it to fully "see," but from 3.1 pro on I've removed many of them and haven't spotted problems.

3.7 Flash scores better than 3.1 pro on most benchmarks, leading me to believe that even if your OCR requires reasoning to interpret text or data, 3.7 Flash is probably going to be better.

3 Pro is quickly approaching one year old. There's almost no reason to benchmark it, especially since a new version of Gemini Pro was supposed to be released mid 2026 and hasn't seen the light of day.

The “pro” moniker means nothing

these models aren’t successors and barely have a common ancestor, they are independently baked in the training oven and assigned a semantic version randomly by someone trying to show initiative but not trying to do on the toes of the last guy who got promoted first

So 3 pro is outdated and will likely never exit preview

The “flash” and “lite” models are the real “pro” in colloquial ideas of fleshed out and capability, at this point.

they’re better, faster and cheaper, larger context windows keeping up with the industry and more

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