What with all the "holy crap update broke it" threads, I thought I'd mention that PA runs much more smoothly now. I'm actually getting framerates consistently above 30FPS. The only problem I've run into so far is that pathfinding on metal planets is seriously wonky. Fabbers will literally walk in the opposite direction from what I want them to build/assist/repair.
As the game progresses and uses more up-to-date and different libraries, some people with older firmware and software are finding that their machines just don't have the libraries to use PA. Then there are also compatibility issues (especially with older OSes, unsupported Linux/Unix distros, and pretty much everything but the latest Mac OS because **** Apple). But I agree, for the majority that have the game running, the clientside FPS is smooth as butter and there are no longer issues with unloaded virtual textures. Good job Uber, you're winning the game.
By my own statistics most of reports is about broken build is from owners of notebooks with only Intel graphics and also from people with dual graphics who forgot or just can't activate it for PA. As Linux user I can report there is few configs where game is broken (unsupported Nvidia Optimus), but that general stability of game and UI is probably better compared to Windows. Probably because Google doesn't support 64-bit on Windows, so Coherent is 32-bit while game is 64-bit. We also have open source drivers (for AMD and Intel GPUs) which is slower than Windows one, but they are extremely more predictable than any proprietary driver may ever be.