I think there is a blurring of the lines in this post.
For the record, putting an M badge in front of your 3xx is just daft in my opinion. However, saying that people with 320s shouldnt put M kit on their cars is ridiculous. People have been tuning, upgrading, modding (call it what you want!) cars since they were invented. To say you shouldnt because its a BMW is just arrogant. I can't afford an M3, but that doesnt stop me from taking styling cues from it. I dont pretend its an M3, but look to upgrade bits and pieces to M sport pieces, because they are better/more stylish, and they fit.
Making your bmw look like you've driven through halfords is a far bigger crime than putting an M badge on your car.
Pre LCI Monaco Blue e90, iDrive, 18" 220M reps, M3 Front Bumper, LCI headlights, Darklines, Eibach Pro Kit [Build Thread]
ICE: DLS R4s, Gladen HG-201BMW-3, Alpine PDX 4.100