Most are going to tell you that Powerdyne is junk. So get ready for the "get what you pay for" speech.
I personally have a friend with great success with one on a fox coupe. Everyone is going to rave about the Kenne Bell - which is great and all, but it's pricey. If you are looking for a descent price/quality/peformance. Vortech's seem to last and produce good numbers. My 2 cents.