I'm sure they are quite comparable, but just wanted to throw out that we had a really good experience with Prime Time Shuttle. Right on time, really friendly driver, clean and well maintained van. For our return trip to the airport, we were the only ones onboard. When I checked rates, Prime Time was slightly cheaper than Super Shuttle, but this was back around Memorial Day.
Riding Splash Mtn at Tokyo Disneyland for the first time as a family!
Nobody had to stay behind for Parent Swap!