I found a thread on this site comparing the 2, but I thought you guys might be interested in what the M3 kids have to say. I think the thread on this forum was much more informative BTW. I have some interest in this topic because I want to eventually get an NSX.
http://www.m3forum.net/m3forum/showthread.php?t=145993
http://www.m3forum.net/m3forum/showthread.php?t=145993