Im actually a big fan of the WGP preset reg for my pumps. Initially I used it because I could get them so cheap, then they won me over with their consistency.
But really most of the regs you see now days are evenly matched. I've got an 05 Ego reg on my cocker and shoots +/- 1, maybe 2 FPS all day. My NXT shocker has an old CP reg, it's +/-2 all day. My NT11 with stock reg is +/-1 or less consistently. Hell, even my DP G3 is +/-2 every time.
Best reg? most of them are as near perfect as you can get now. It's better to ask the worst reg. IMO that is CCM's. I love their guns, but their regs are just craptastic.