If anyone is thinking about this I highly recommend it.  I just changed from my last set up to this and what a difference.  Takes off smooth like a car and has tons of power.  It pulls so much harder all the way through.  One thing I hated about the last set up (typical b-3 weights and primary spring) was it would poop out on really long climbs as ALL of the power was down low.  It would still pull but I could feel the loss of power.  This holds the power better through the rpm and puts so much more to the ground.  According to MSC it'll also cool belt temps because of the extra grip on the belt.  I guess we'll find out.