What the hell...does anyone understand exhaust flow? We're talking about taking out the high flow cat, and putting in a straight test pipe, correct? And we think you're going to lose torque? Sure, the high flow cat flows very well compared to the stock cat, but there is still some restriction there. When you get rid of that, you get rid of the backpressure and add velocity to the exhaust, since it doesn't have to slow down through the cat.
When you reduce backpressure and gain velocity, you gain TQ and HP everywhere...low, mid, and top end, plus the turbo can spool faster with that lower backpressure.
Now, is the difference going to be huge? Will you be able to feel it? Probably not, but there are only gains to be had...you won't lose anything.
You're taking this large brick out...
...and putting this free flowing pipe in.