I'm going again this year and I'm sitting in the stand mid track and will be shooting from high up. I shot last year from the Super Seats and it sucked. I took my 300mm with a monopod and no problem. I was glad I had it as I was able to snap a few shots of John Force's accident (so glad he is doing well this year). Other than those shots I didn't get any reall good shots from where I was sitting. As DavidTX said, don't go to the fence line or you will only get the tops of the cars with the concrete wall.
