Don't bother messing with the test pipes unless you plan to switch out the stock exhaust. And there's probably no point in changing out the test pipes unless you want to swap for HFCs. You can, of course, always switch over to the ART pipes or something else. But that would just be spending money for a slight change in exhaust tone.
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2011 370Z 6MT Sport Gun Metallic | ARC | CJM | Ecutek | FI | Fujimura | R2C | SPL | Stillen | TWM | Z1 | ZSpeed | |