If you buy new a lot of companies actually have warranties on their catback systems. Nismo one barely gets any power at all, and barely sounds any different. I'd recommend the Invidia Gemini if you don't like loud exhausts, as that one is fairly quiet. Also makes like 3x the power of the Nismo one, if not more lol. If you want a loud exhaust, there are plennnty of other options out there
Fast intentions, Berk, Motordyne, just to name a few.