Somebody on Reddit who's beta testing Fable Legends confirmed that it also has those limitations, as does Minecraft, which means this almost certainly will have as well.
https://www.reddit.com/r/pcgaming/comments/45mkib/quantum_break_getting_no_steam_release/Windows 10 store exclusive means it is built as a windows app which means:
No SLI/Crossfire,
Windows 10 store download is buggy,
No refund policy explained,
Vsync is always on,
Always borderless fullscreen,
Game files are protected,
Can't launch it via the exe (So adding it as a non steam game will not work)
No fps/hardware monitor software works with it,
You need to take control of the folder as admin if you want access to the files
Mouse software which lets you create custom binds for each game doesn't work
Say bye to using sweetfx and mods
EDIT: I'm not making this up or taking it from other sources. I'm part of the Closed BETA for Fable Legends and have Minecraft Windows 10 Edition. I've came across all of these issues
Why do Microsoft always have to find a way to spoil their PC gaming efforts? They're so desperate to control it within their own little ecosystem, and it's never going to happen. Games for Windows Live was a miserable failure, and the Windows Store as a platform for delivering "real" games will be as well if these limitations aren't addressed.