Just about any time somebody does better than Andrew.
In Season Five, Jakob completed the Gimble challenge faster than Andrew.
Similarly, Dean from Season 6 outperformed Andrew in the Trailer Challenge.
Sean did the same thing in the offroad challenge in Season 2
Aaron's public drive from Season Seven, which was almost perfect (aside from rolling through a stop sign early in the drive). Seeing him grinning from ear to ear as he drives as a normal driver for the first time since nearly being killed by a woman who failed to observe a stop sign was truly a magnificent sight.
Chris Ferguson, the "winner" of season 1, returns in Ever to perform a nearly flawless performance in the assessment challenge. He ends up being the first graduate of that season.
Hell, he's the first person in the entire series to graduate on the first episode.
One of the final challenges on the Ever season finale was to reverse down a narrow pathway lined with cars, do a reverse slalom, turn around, then Do It Again Forwards. Kevin somehow manages to pass it flawlessly. It's unfortunate that the same couldn't be said of anything else he did...
Thomas' performance in Season 3. Nailed every challenge eventually, graduating second, then winning the first race he entered. Certified Badass Driver
In the Season 10 premiere, Mariah admits to being a drunk driver. She proceeds to laugh it off in the confession cam and then when she arrives at the rehab centre, she makes a further lighthearted comment about her drunk-driving. Andrew then proceeds to thoroughly chew her out, citing that many people who are watching this have had friends or family die on the roads. It's somewhat satisfying to watch the wind being taken out of her sails a bit.
Hell, Andrew doing this to any of the drivers who engage in stupid behaviour on the way to the rehab centre.