We've been using the red Andersen levelers for years... first with our class C, now with our TT. Never had any issues, other than soft ground once. Also carry 2 pieces of 2 x 6 that are 4.5' long. This gives us another three inches and helps on the rare occasion when we're on grass and need to spread the load a bit. The boards are sized so both axles fit within the 4.5' legnth. We always chock the wheels on the other(high) side and use BAL expanding chock between the wheels that are on the levelers. All very stable and never had any issues.