I just don't trust a 12 volt compressor. May be fine to "top off" but what if your tire is FLAT and you need to run 80 psi into it?
I carry a 12 volt compressor in each of my cars, but for the MH, no way. I carry a Sears Airboss compressor. Small but powerful 135 psi, takes up mayby twice as much room as a 12 volt job, costs a c-note when on sale. Air's up my class c tires in less than 4 minute's. On the side of the road away from power, kick on the genny and I'm good to go.
Also carry a Lowe's Kobalt 350 ft/lb electric impact wrench for the wheel lugs, 12 ton bottle jack, and a Stop & Go tire plug kit. Also, half a dozen air valves for the valve stems and the small tool to insert them.
Basically I can repair or change a tire without having to wait for hours for my roadside assistance to kick in, and usually they won't change an inner duelly tire.
Rather carry this stuff and not need it than be stuck waiting for help. And, I've used my equipment more than a few times helping other RV'ers that I've seen on the side of the road.
Grumpy