Does anyone know why the 19" wheels are not offered as an option with the M3 Performance? I'd really rather not deal w/ switching out the wheels during winter if I get the upgrade package (which comes with summer rated 20" wheels). The M3 Performance comes with 18" wheels standard. But no 19" option? At this point, if I want the 19" wheels I'll have to buy and extra set of wheels for $3,500. But then I'd have two sets of wheels. Thoughts? P.S. If you think "you're crazy, if you get the M3 Performance, then you should get the 20" wheels", I'd like to hear that too.