When I buy my tickets for Indy I alternate my seat for each night:
QF: up high on the 50, so i can get the big picture and see the drill
SF: in the middle section, usually 45 yard line, cuz i like the sound
Finals: down low, usually on the 45, i like to see the details. and the emotion from finals night is amazing from down there. you can feel the crowd/performers reaction. tried sitting up top for finals in 2009 and it wasnt the same.