So let me get this right, you're going to go AGAINST recommending an aftermarket midpipe? WTF mate? 
Take a look at the stock one. Take a look at a Magnaflow X (or any other aftermarket midpipe). Notice how much the stock one sucks.
Better yet, do longtubes and an offroad X. Proven gains of 15-20RWHP (even a bit more in some cases, I've seen 22-23RWHP) over the stock exhaust system.

Take a look at the stock one. Take a look at a Magnaflow X (or any other aftermarket midpipe). Notice how much the stock one sucks.
Better yet, do longtubes and an offroad X. Proven gains of 15-20RWHP (even a bit more in some cases, I've seen 22-23RWHP) over the stock exhaust system.
. Anyone have one of these pipes feeding a borla cat-back?