It is not always about that with BMW M cars. Take the example of 545i (V8) vs M5 (V10) or 645ci (V8) vs M6 (V10). The V10 requires more room then the V8's and runs hotter yet no functional scoops or power dome. I believe that is because they like to go a bit conservative with M5's and M6's. Where as M3 are more down market and attracts younger buyers and thus more aggressive profile.
Originally Posted by M-Power111
thats a good point however im one who likes things on a car that are functional or have a purpose in some way, having a dome with no use is fake. that said i do think it would look nice on the new M3.