It's very hard to measure the performance in the Win 10 version, but it seems to be exactly the same so far. I'm on a Titan X and playing on a 60hz TV, with settings all maxed out (except AA, using SMAA), and I haven't noticed any drops yet. The fact that it can't run in Exclusive Fullscreen might be a factor once I get to the more demanding bits though. I'll try to be more scientific about it once I've actually finished the game. Save files doesn't seem to be cross compatible between the versions either, so I'm going to have to complete the game twice too. We'll see, focusing on finishing the game first
Pretty sure, yes. Caught me by surprise, thought there was something wrong at first, haha.
EDIT: Just started up the game now, and all the save progress I made last night, about 3 hours, seems to be gone. Might just be something wrong on my end, but here's where the locked nature of the app ecosystem really starts to piss me off. I don't even know where to look for the files.