Originally Posted by CanAutM3
The shorter sidewall will also make the tire stiffer, but may also make the tire less compliant to adhere to road surface imperfections.
For the race tracks the shorter sidewall will be of benefit as discussed.
For the drags however a taller sidewall is preferable. This is the reason why drag slicks have such tall high profiles, you want a soft flexible sidewall to allow more contact area and grip on take-off.
For the street, depends on the quality of the streets in your area, if you do a lot of country driving I would go for the 35's.
2010 Silverstone II E90 M3 Competition Pack M-DCT Sedan
BBS LM-R 19x9.5 ET32 & 19x11 ET25, TMS 12.5mm Front Spacers, Michelin PSS 255/35/19 & 295/30/19, aFe Pro5R Air Filter, ACM Test Pipes, BPM Stage II Performance Software, BPM DCT Software, BPM Feature Coding, LUX H8 Angel Eyes, Matte Black Front Grill, H&R Sport Springs, Akrym Style Front Lip.