A shop fabricated exhaust is fine as long as you aren't paying too much. But it sounds like they are still going to be more expensive than the most common off-brand exhausts like Beluga, Top Speed, etc which generally sound acceptable and have decent fitment for the most part. I wouldn't let some shop with unknown Z experience fabricate anything for me.
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2011 370Z 6MT Sport Gun Metallic | ARC | CJM | Ecutek | FI | Fujimura | R2C | SPL | Stillen | TWM | Z1 | ZSpeed | |