I'm not exactly sure, but somewhere around 6,000 miles the exhaust sound became more throaty on my E93. I had thought about getting a mod, but now am glad that I waited. It's loud enough for a daily driver -- I don't want it to sound like a Harley-Davidson with open pipes.
M3 Cabriolet; Le Mans Blue Metallic.
. . . .Munich . . . >. . . .Houston
When one wants a cabriolet, is there really any other choice than an M3? No. No, there's not.