My KeyCool 87 works very well, I was very pleasantly surprised. It has MX reds and the white case. Not a single problem with it.
F1 to F4 probably do things like Windows Explorer, Internet Explorer (maybe), Calculator and music player, although as I primarily use it on a Mac these keys have no effect.
F12 is a winkey lock - it illuminates when the Windows key is disabled - useful for gaming (but again useless on the Mac).
KeyCool is also standard layout, so almost any replacement keycap set will fit.