I have them, as mentioned above, if left aired up, and no load it will be rough, I also got a used semi air tank mounted under the pass side truck bed, and a mechanical controller (dual needle singel air gauge) that allows me to air up/ down from in the cab. with the tank aired up to 120-150psi, I get lots of use before needing to air up the tank, I could not justify the cost of getting on-board air, but the tank and controller only cost about 120$.as an added feature I installed an air quick disconnect that I can hook a spare air line to so I can air up a tire if I need to