I have a 30' Jayco Jay flight. This is our first travel trailer. I recently leveled our trailer and when disconnected from my truck it rolled back about 2" and partially crushed my plastic wheel choc...
Plastic wheel chocks are more likely to slip than the rubber ones, especially if the surface is smooth and wet. I use rubber wheel chocks with the X-chock. With that and the 4 stabilizers down, it isn't going anywhere.