I'm running the six pound powerdyne on my stang and I love it. It's a very simplistic design being internally belt driven. The belt will break eventually and you will have to replace it. It costs about $60 for the belt. I've changed one myself it's fairly easy. If I had to do it over again, I would get the Vortech A-trim. It's inexpensive and it's a very reliable blower for about $1900. Tapping the pan is no big deal. The A-trim is also easily upgraded to 10#'s with readily available pulleys. Six pounds is plenty for stock heads and intake. If you open up the heads and intake you're going to make some serious power. With good heads and intake and matched camshaft, you could probably make about 450 horses with that A-trim. That's plenty for most mustangs. It probably flows around 900 cubic feet per minute. They also sound bad!!
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92 GT, 4:10 gears, centerforce clutch, 6# powerdyne blower, bbk h-pipe, flowmasters