The Jackson Racing website has their dynos posted. If anyone can get the most out of their SCs it would be them. The numbers are alright but not *WOAH*. Turbos seem to be putting out better numbers; if you want larger HP numbers.
I've been N/A for a while and am looking into a SC myself. I'm liking the Vortech but am still researching. The forums aren't too much of a help either, everyone talks bad about them but nobody seems to have any experience owning or trying one.
Oh well good luck.
The JRSC is a nice piece though it's built well and JR knows their stuff. I have a friend with an si that has a JRSC. It kicks some a$$.