i have 2 air compressors
a ridge rider which is about 12 years old. 160LPM and a 45min duty cycle. after about 1 year of use the pressure gauge stopped working, unable to get a replacement.
a Ryobi 18V ONE+ Cordless Air Inflator. it comes with auto shutoff once desired pressure is reached.

how i use them: lets say ive been on sand and down to 20 or even 10 psi. i use the ridge rider to do the bulk of the inflating. cause the gauge doesnt work, i just inflate one tyre to what i think its about 30psi. i then connect the ryobi, set it to 40psi (this gives 38psi).
while the ryobi is topping up the first, i put the ridge rider on the second tyre. repeat for third and fourth tyre

the ryobi on a 2aH (5 and 6Ah also avaliable) battery can take 4 of my 4wd tyres from 30psi to 40psi.

if either air compressor cark it, i can still use the other one to put some air in all the tyres so i can slowly drive to a servo.