The prices vary on the kits:
Hahn system $3,400 Up to 350HP (with modifications to fuel system)
Mr. Turbo Wouldn't buy, out dated, slow spool, and oil return pump.
MC Express system $5,800 to $10,000 320 to 443HP (Holeshots system?)
Anderson system 7,000 350HP
If your on a budget, the Hahn system works the best for the buck. You can make 300 HP on pump gas and it drives just like a stock bike. No major lag problem, complete linear and controllable spool, even in corners! Contrary to popular myth, turbos don't just come on and go out of control!! You can control how much boost you want even in corners and straights and if the bike is properly tuned drives better down low then a stock bike period!!
For more info on the Hahn system:info: www.azbiketech.com
For more info on the MC Express and Anderson systems:
The bottom line is, don't listen to someone who has never ridden a Turbo Busa for opinions, they just don't know! Do your own research for your application.