I've been running SFOS on FP2 for a few months now as daily work phone. Majority of it really works with no issues, and like Feathers said, the speed of operation is a world ahead of Jolla. Unfortunately I missed the Jolla C train, so can't compare with that.

There are the occasional glitches, like touch screen randomly becoming unresponsive (random ragetapping all over works to get it back though). Speaker volume is an issue, indeed, too.

I deployed the Maps app from my original Jolla. Works fine.

But looks like we're still stuck on 2.0.0.x. Not sure at all whether anyone is working on anything newer, I understand 2.0.2.x is around the corner?