Hello from a fellow Missourian!
The Nismo uses an H-pipe rather than the base/sport Y-pipe and deepens the tone a bit, however there is no real volume gain.
The Nismo's higher factory HP comes from a tune and the exhaust. So without a tune I'd expect minimal improvements, especially since it is not as free-flowing as an aftermarket system.
You can source a good one for around $500, but at that point I say save a bit more and get something that will really improve the sound.
I debated getting the Nismo, but went aftermarket (Bassani) and have zero regrets.
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AAM | Dynosty | Ecutek | Eibach | Hawk | H&R | Nismo | Stillen | Stoptech | Z1
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