Just found this on PH on a discussion about the M135s enhanced cabin sound:
"Yes I've owned many other M's and actually (ironically) I don't like the E46 csl because I think it sounds too digital. I think the single vanos 3.0 e36 was the best sounding of the n/a six cylinders. It just sounded more raw and angry, less controlled/metered."
http://www.pistonheads.com/gassing/t...2E%2E%2E&mid=0
Page 7.