I'm generally there every year, but usually early in the week when most of the cars
are still there. Not much BMW stuff usually, but its a great people-watching event,
which you do not EVEN get a sense for from the incessant speed coverage on cable.
If you go early in the week (like day 1 or 2), the massive tents out back are full of cars,
the atmosphere is that of a HUGE body shop (a LOT of freshly-painted cars out there)
Have fun!