Doesn't sound bad. From the poor quality welds, I am assuming it's a pre-production unit. Still the craftsmanship seems extremely poor compared to the Akrapovic and many aftermarket exhausts. That's quite disappointing coming from M.
Current: 2009 E90 M3 | SG | FR | 6Speed | Akrapovic Evo | JRZ RS1 | StopTech Trophy | Cantrell Brake Ducts
On order: 2016 F80 M3 SO | AB XT1 | ZCP | etc.