We rented a van with driver through Disney (4 hours, party of 9). The driver was great and only started the clock when we actually began the tour. The van was very well maintained. He listened to our requests (i.e. no ruins or churches, but stops at nice beaches) and didn't force us to stop as his uncle's souveneir shop or something like that. Everyone had a great time and it was nice being back on the ship by 1 pm. Last year, we took the ferry to the mainland, and it was a relief not having to worry about that long, rocky ride this time. I would rent van plus driver through Disney again: it is probably more expensive, but the peace of mind makes it worth it to me.