The project to remove the triggers and replace them with switches was far more about stress on my old-man finger joints than anything else!
I built one with a DIP last year- without messing with the triggers and bumpers; which used momentary push-buttons for the extra buttons. Frankly I never liked the feel or response of that type of button. These sub-miniature microswitches take very little force to operate and never fail to work properly.
It does mean I can aim and shoot quicker; only time will tell how much that matters!
Original shoulder buttons now emulate the Back (left, for BF) and R-stick (right) buttons.
The buttons underneath can be set to emulate RB, RS, X, Y, A, B, LB, LS.
I had originally intended to replace the D-pad and face buttons with microswitches too... but decided I couldn't be bothered. Next project me thinks.