My jack, Kilroy, was trained to drive before we started breeding him. He loves it! I don't have any problems getting him to go as fast as I want. My problem with him is getting him to WHOA and back up. We had Bonnie talk to him and he has started backing up.......slowly.
Each donkey is different. Some of the bigger donkeys we show against don't like to go faster than a slow walk. At one show, we had the judge laughing so hard she was crying during a pleasure driving class. It was Kilroy against 2 standard donkeys. Kilroy got first because he was the only one that kept moving! It was pretty funny.
I do show Kilroy. He has been Grand Champion jack all but 3 times in 7 years. One jack beat him 2 yrs in a row. They gelded that one shortly after.