I went with the Vortech on my daughters car for a few reasons. 1. She has an auto and I was a little concerned with the strength of the auto 2. I wanted less low end torque to minimize wheel spin and the expense of needed suspension parts and 3. Didn't want to add more than 100 to 125 hp to her car. She's drove it a little over a year now with no problems. As for Brenspeed can't say anything but good things about them. I'll be going back soon to have them put a Saleen on mine for all the oposite reasons of my daughters. I want the low end torque, I have a 5spd and I want around 475hp max so I don't have to go with the forged bottom end.
06 GT Satin Silver 5spd
Performance: Vortech S/C, Brenspeed tune, FRPP Exhaust, Hurst Shifter
Beer is proof that God loves us - Benjamin Franklin