Everest for us.
It's amazing now when 99.999999% of the Guests go to the left to get on FOP and the remaining 5 people walk over to EE to ride it over and over and over and over and over - front, back, middle, upside down - whatever we want- since nobody is there.
FOP is a very different and interesting experience, but I guess for us EE is our "thrill" ride.
The Safari and Dinosaur hold special places in our hearts as well, but it's EE that we enjoy multiple times whenever possible.