My brands day was through Focus events, it was an open pitlane event. They didn't like people timing during trackdays so didn't get any laptimes, I don't recall getting overtaken much other than by Ferrari/Porsche 911 down the straights. Quite a few people lost their cars and spun off, they had a policy of asking people to leave if they lost it and had to be recovered because it ruins it for other people while they recover vehicles. The biggest issue I had was headroom, I couldn't get a remotely decent driving position with the crash helmet on.
Alfa Romeo GTV T-Spark