Most will probably argue for teh powerhouse because it is bolt up and the traditional thing. I am working on a STS rear mount kit on mine with a shop that is going to come out alot cheaper than a powerhouse kit and get the same if not better numbers. It is cheaper because I am getting the universal kit for 2800. If you do this you have to get custom piping with the install but that is not much more than an install. You also must get a custom tune which will cost a bit more but most people want to do this anyway. So in short... I could have got the powerhouse kit for like 5100 and had it installed for 500. I am getting the kit for 2800 having it installed for 900, buying a meth. injection kit for 200, boost gauges and a cluster for 250, and 800 for the tuner and tunes and my total is around 4950.
My vote is STS.
My vote is STS.