I have the same leaking air chuck. The gauge on the compressor is not accurate at all and tires end up over inflated. The single tire inflation hose is cheap and doesn’t get a good seal on some valve stems. I have yet to use the 4 tire inflation system. I’m not very happy so far for what I paid.

I've been looking at this unit and the Moreflate...they are probably the same thing. The 'M' mode is for filling 1 tire I think. So I don't think there is an actual "manual" mode. It shuts off to measure the pressure to see where it's at and if it needs to add more air. I always find it fascinating to that air passing through a hose will make it hot but they all do that. I have a portable fan that I keep in my 80 series Land Cruiser that I direct airflow over the compressor that I have to keep it cool. It makes it so you don't have to wait around to let the compressor cool down which you couldn't put back in the bag if it was hot.

that fitting leaking is not good but the overall system is better than morrflate and the moab air compressor which are similar. So thors needs to do some QC on those fittings. Saw them at the CAlifornia Overland show this past weekend and was going to pull the trigger in this unit but decided to wait.