My Wheeler mtn bike came with the rapid fire shifter so I guess that means i have a "fast rise derailer?" I dont know but the problem I had with it was the fit. I found it to large with all the other controls. Just didnt feel natural to have to move my hand from the grip to shift. The twist shifter keeps the clutter down and works very nicely- feels right to me. I rode for awhile with two levers until I tried the dual brake lever and well- I will never go back. Especially on the bikes I sell- simplicity is key. Amaze's me how so many people have no idea what a clutch is, let alone put two levers there to choose from!