I hear you. I'm in Chicago, and the roads can just be brutal in the Spring. That being said, I don't drive much since I commute to work on public transportation (15min train commute ftw!) or ride my 10 speed. I mostly drive to my buddies that live on the edge of the city, to get cat litter/food for my fiancee, and most importantly, to get the hell out of the city....far! I avg about 4k-6k miles a year on my cars =]
Anyways, the other consideration is that when doing this type of thing, it's time to do the control arms, cabs, mounts, etc... It adds up fast! Just doing HDs with the replacement parts will cost you close to $700, and that's without the M3 CABs. All this does make the stock springs oh so appealing to me. My car is feeling a little floaty, especially 80 MPH+, I don't notice it slower so much. Think new shocks are definitely in my short term future :rolleyes: