It's a bit soft visually, even at 4K (make sure to set the desktop res first for Unity) but that's the aesthetic they chose. It ran flawlessly for me on my 1080.
Are they forcing some kind of aliasing?
No issues whatsoever, outside of the 360 pad not working with Steam Link. Game only supports the Steam controller so far.
But performance-wise it was silky smooth.
I would think that would be supported at the hardware level for the link.