sct and predator are pretty equal, try the search function there's a ton of info here....The can tune's arent the greatest...If you get them customed(mail ordered) or dyno'd tuned not much of a differance. All depends on what product your tuner prefers. I would finish your bolt ons 1st before a tuner unless your getting gears...In that case you might as well get it for the speedo because you can use it in the future when you decide to tune.