While using the one in my Legacy, I took it offroading in the Pine Barrens of NJ. I dug all possible bottom part of the car through sand, at one point I got stuck and had air under all 4 tires with the body sunk in the sand. Got yanked out and double checked the valve, no problem.
When driving with it on the SVX late one night, I re-hit a deer at about 70mph. It was already dead on the road, I saw it at the last minute and didn't have time to avoid it so I centered it. I felt the whole car lift as I rolled the deer under me. I never really even lifted off the gas, just checked for smoke and dash lights. The next morning I pulled it onto ramps, there was bits of hair stuck to most parts of the chassis, but the valve was fine.