9:15ish is reasonable with your own car trying to get to MK at the end of the night. MK just takes longer to get from car into park than anywhere else because you have to tram, ferry/monorail and then start security and going in to the park. 10pm worst case scenario in my mind but that would be rare to have that much traffic leaving HS. because of the time from car to MK with the extra ride on somethign in the middle, I find the bus to bus to work best when MK is the destination for time. It's never really comfortable with how many people they pack in at close of another park. any other park, car is no brainer.