ADP will probably require you to have checkouts for landing at both Catalina and Big Bear. Catalina has a cliff at the threshhold (painful if on a low approach) and a hump in the middle. As Jetagehobo has said. the problem could be that you get an illusion that you are running out of runway when only half way along it which means that, there is a risk (in the view of ADP) that you will brake like fury on landing or pull up prematurely on t/o. Big Bear is up in the mountains at 6748ft MSL which makes for interesting take offs towards the trees at the North end of the runway especially when it's warm.