Yeah driving to vegas in the M3 is really nice. The power really comes in handy for passing and not getting stuck behind slower traffic.
I don't drive crazy or anything, but last time I went, I left at 5pm on a friday and was in bumper to bumper traffic for awhile, but still managed to get to the hotel by 8:15ish. I was pretty happy with the time.
Getting stuck in the middle of nowhere is always a thought in the back of my mind, but keeping a spare just isn't realistic. Barely had enough room for luggage.