It all depends on what you're after.
The DTM wing is an unproven design, as opposed to the M3 LTW wing (knockoff or not...).
Personally, I'd take the M3 LTW wing, but that's because it's actually proven to work (and my car is dedicated as a track car).
I actually have one of the LTW wing's on order (though Heaven only knows when it will actually get here...).
On ANY 4-door though, wings are going to stand out quite a bit. If you're not planning on tracking your car much (or even at all...), then I'd suggest the factory wing / M3 low-rise wing (such as I have listed in the For sale section...).
The DTM wing is rather Ricey, in my opinion.
I'm not really an asshole, I just play one on the Internet