You can buy a kit and install the parts or have it done and get jaw dropping performance with the right tune. There is the rub. A complete build includes all fine tuning needed to meet the goal set in the planning process.
Yep, I said planning. The customer has to be part of the planning, it's not drop it off come back when I call and go "Holy crap that's (not) exactly what I wanted." at WAR Performance. Your bike, you ride it, your desires and goals are what go into it. Period.