We were picked up exactly on time, all ran smoothly with no problems. Pleasant driver!
The only comment I would make is that we were advised that we would be picked up at 13:25 but weren't flying until 19:00 hours. This was somewhat early but didn't bother us and enabled us to spend shopping / eating time at the airport.
Shuttle was ready when we arrived, had to call at 2 more terminals to pick up passengers, then we were on our way. Traffic was heavy on the interstate so the driver took an alternative route. A bit bumpy but got us to our hotel reasonably fast.
Our return journey to JFK started very well with the driver turning up 20 minutes early. Good start on a busy day. He was then let down by other guests not being at the next pickup! He stayed calm however and made good time to the airport. Very busy traffic but arrived with plenty of time to spare. I would recommend this highly for piece of mind at the end of your holiday. Good value for money.