Its a piece of crap. Plain and simple. Blunt and to the point.
Most of the Titan guys that have bought it have since sold it for UpRev. Now that handheld tuners are out there, the VKpro is just out dated.
Heck, the guys with the superchargers that are forced to use it have started to use UpRev instead. They were having lean condition issues with the VK unit since they usually started to add headers and exhaust which you would think is the norm when you add a supercharger, stupid narrow minded Stillen.
Side Note: This is why they have such a crappy reputation on this site. They supercharger system has issues (price, efficiency (mpg and power) and dependability) and the VKpro is just crap.