It's pretty well true. A 420a sporting a stage 2 Hahn kit will out accelerate a stock GS-T any day of the week. Hahn uses a custom version of the MHI 16g. You'll spend around $4000 for a stage 2 kit shipped to your door.

OP: 10 seconds? You're looking at breaking Hahn's record at that point. Not to mention the fact that you'll be into it for at least $6000 at that point. I'm not trying to dissuade you from boosting your car. (I used to own a turbo 420A) As far as reliabilty goes, pay no attention to the previous comments, a fully built 420A (tuned properly, of course) will be very reliable. It's your money, do your research before jumping headlong in to this.