MBP Bootcamp for Steam, Win 7 or 8?

Title pretty much says it all. I would like to run Windows on my 15" MBPr to play a few games. Are there any known issues with gaming on Win 8? Steam and 8? Especially through bootcamp? I would like to go with 8, just because I find it pretty interesting, but I'm really only going to boot Windows to play games, so is 7 the safer choice?

Also - do you get native support for the 360 controller when running Windows through bootcamp?