Avoid Hipshots. The tuners are great, but the Heritage headstock is slightly thicker than Gibsons. The Hipshots are too short.
I'd stick with Grover, Kluson, Gotoh, and Ratios.
You can get the Grover 502s with several different buttons. I usually go with the nickel keystones, which are the 502NKs. I am also curious about the Ratio tuners, and will be watching this thread to see if anybody has used them.