All I can say is SW ran like a 10.7 (corrected) right out of the box and he was tickled to death with the car. For a "bolt on", this looks like the way to go. As I recall, SW had a few other tweaks to the car... rockers and maybe slightly massaged heads? Maybe Sean can add the details.
The CNC machined intake was very nicely done, and as a whole, the supercharger is packaged nicely, with a high level of fit and finish.