I put the Big Dot tritium on of all things, a Colt Pony Pocketlite that I had Scott, McDougall, and Associates perform a number of modifications on. They were pushing the miniature Novaks but still put the Ashley's on at my insistance. I personally like them, but then I don't plan (as far as I'm able) to shoot beyond 10-15 yards with this pistol anyway. I find them exceptionally fast for flash sight picture use. I also tried Novaks relatively new half ghost ring on a Kimber to see if that presented a better option for drawing visibility to the front sight. IMHO, although this setup is fast, I think it creates more vertical dispersion of shots that that afforded by the Ashleys. With that said, in my experience, though you can hit at 25 yds with the Ashleys with studied concentration, it isn't their forte at least for me. The big dot just covers too much target at those distances. I also purchased Wilson's Combat Pyramid sights to see how they fared, but I'd have to say the Ashley's win for near contact distance out to say 15 yards, the Wilson's or the half ghost rings to 25 yards or so, and plain old black sights for paper targets.
Just my experience,
BT