I've been driving my car for 3 yrs. with summer tyres, no real problems except I got stuck on a hill once, no accident nor slipping into intersections. You have to be driving real fast for that to happen, or you really need to get your brakes pads changed.
It is very true half the people with bmws don't know how to drive their cars in the winter, last year was especially fun when I was on queens Blvd. , so many bmws going sideways and I saw g35 all wheel drive do a 360 in the middle of the road what a trip.
I drove 30 miles this morning (round trip) to the doctor no problems, 19" csl + summer tyres, went into a corner too fast back end slid out but dsc was there to correct the problem
if you don't know what to do, yes I definitely suggest keeping the car at home, too much counter steering involved driving with summer tyres :-P