I've heard allot about tramling on the OE 235x4 setup and wonder why BMW changed to 225/45 and 245/40 on post '95 cars. Was this to reduce the tendancy of the car to "follow" every rut in the road or did it have more to do with oversteer? I have all 7.5x17's and need new tires. I was thinking of a staggered setup like 215/45 in front and 235/40 in rear. Any comments or experiences? Should I try this setup or will a good tire the OE size suffice? Thanks!