[Templar]

Performance, no. No difference really.

Looks, yes. The coupe looks better, to me anyway.

For some reason, when I see an E90 M3, I think of a 3 series. The sides and the rear just look too much like a 3 series to me. For some reason the E92 M3 really stands different from the regular 3. If I am driving and I see one I always say, "Man, was that another M3? I'm not sure." Of course if I get a better look I know right away, but on first glance it's hard to determine.

When I see a M3 coupe I KNOW it's a M3 vs. just another 3 series.