I wasn't that much into sound until I had my 987S. The sound was awesome. It went from a nice deep rumble at low rpm's, to a nice sporty sound mid range to a great top-end shriek - bone stock. No 6-cylinder soudns better than a GT3, but the vanilla Boxster S was pretty great.
The E90 M3 was intoxicating at the top-end and still nice enough down low. I want my car to sound great. I'm not buying it primarily to get good track lap times or beat other cars at the drag strip.
In the end, like most, I will use less than 50% of the car's potential most of the time. I want my premium performance car to feel special doing even mundane things. The Boxster did that and a big part was the great sound behind me. If my car won't sound good and I have to take solace on having extra power beyond a 335i than I can seldom touch in day to day driving, I'll put my money into a real sportscar, even if it's used and I only drive it sometimes.
I have an M-Sport 328iT and it is a great daily car. Actually, beyond only occasionally wanting more power, the big downer is that it's too damn quiet.
I'm hoping to shoehorn 2 or 3 kids into an F80, but if I can't get the whole experience, I rather drive the GL everyday to drop off the kids at daycare and get a used Boxster or 911 as a sportscar.
When I almost bought an E90 M3, the big draw of the M3 over a regular 3er was the exotic-sounding V8 that could rev to the sky. I'm willing trade the 8500 rpm redline for massive low-end torque, but I will not compromise on having an engine/exhaust note commensurate with a $70k performace car.
My opinion, of course.