I've tried many many pedals over the years, some even rare/creative designs, but I always seem to end up back with the Speed King, with the Ghost a close second. Simplicity seems to work & feel best to me. Some pedals have many, many adjustments to them for the drummer to tinker with to get it "just right". Others, like the Speed King and Ghost only have a couple of adjustments, and that's for spring tension only, and that's all they need. When you get it right the first time, why mess with it by adding all kind of adjustments?
I call them the Charlie Watts of bass pedals. :D