I guess I will speak for Powerdyne since I am one of a few Powerdyne owners who hasn't had any problems with the blower as of yet
(knock on wood). Yes, believe it or not, we are out there. I have over 4,000 miles on it, 39 dyno runs, and just under a dozen quarter mile runs without a hiccup.
With that being said, the BD-11A is an entry level blower (850cfm) with little room to grow. Everyone, just like me, wants more power eventually and going over 9psi on the belt driven Pd could put the internals at risk. On the bright side, the belt and bearings can be bought for about $100 and the rebuild can be done in your garage.
So unless money is really an issue, I always recommend a blower you can grow with, like an S-trim. You just never know what you will get with a Powerdyne. It seems some last forever and some break right away. Good luck.
On a side note--Your best bet is to listen to those with ACTUAL experience with superchargers. There are some (actually one person) on this website who believe because they read certain websites (Vortech, ATI) that they have expert knowledge on the subject. Just a warning. Again, good luck.