Personally I think the M3 vents ar to big for the 8, they are to high, and I think this shows in Steve840's picture, they are to dominant on the wing and are out of proporsion with the 8.
A vent 3/4 in hight might look alot better, or even better, the Z3/M-Roadster ones (less chrome, more shark gill like) might also look alot better.
Still say sell them, but by all means, it's you're car, do what ypu want.
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@Steve840
"I hear what you keep pointing out BUT "each to there own" "
It's his car and he can do what damn well he like with it, but he asked for our opinion, and he got mine.