I've got the xi version, and with Conti DWS's to boot (all seasons). The car handles beautifully in snow, but the issue, as you stated, is the ride height.
Anything more than 5 or so inches, and the car becomes the Ultimate Plow Machine. That's on an xi as well, which has a higher curb height. The grinding noise will drive you insane!
2006 330xi | 6AT | Navi | Premium | Cold Weather