I agree with the sound not being up to par with the S65 V8. Everyday the weather is nice, I put the top down or the windows down, turn down the radio, and listen to the engine. It is one of the reasons I love the car so much.
Having said that, I would think the exhaust on this car is not likely the finished product and still has a year before release for fine tuning. Also, it seems to me that this driver was not pushing the engine as much as handling. At a few points, the wheels were squealing from what seemed more like aggressive turns, without necessarily pushing things.
I'm not a racer, just offering a thought. You all can tell me if I'm crazy. Just didn't seem like this car was really being DRIVEN.