As the one who started this long-running thread nearly a year ago, I just wanted to say that I continue to be very pleased with the throttle response improvement that one gets with this device. I had not driven a "stock" Xfire for the past year until a friend recently bought a "new" '06 and I had the opportunity to drive it in a side by side comparison with my car. I was impressed - as was he - all over again with the difference in performance with and without the SB... If you can't tell much difference with installation of a SB over your stock car, then something is amiss... IMHO, there is just no other plug-and-play device that gives such return on the modest investment cost of a SprintBooster!

...And, NO, I have no financial interest in these things (darn it!)! In fact, my SB cost me considerably more than everyone else on the forum, as I ordered directly from Athens!