Is the 121" kit worth the money it cost? or is a well set up 116" or 111" just as good. By well set up I mean intake, exhaust, cams, throttle body, injectors, valve springs and some type or fuel management Dyno Jet, Power Commander. I am looking to buy another bike probably a Springfield Dark Horse. I am just wondering would i be better off just tuning up the 116" it comes with or is the 121" really worth it?