Hey!
Personally, I wasn't a big fan of Steam Big Picture due to various reasons. The first and foremost is that GameGO has configuration for pretty much any aspect, from grid sizes to backgrounds and sounds. It's truly something for the perfectionist.
In the feature, it should be easy to add emulators (+ roms) and automatically get installed games and download banners. So at the moment it takes a while to set-up, but in the future it'll be easier to use than Steam Big Picture.