i had a viair that worked off of the cigarette lighter-and it was junk.but this 440P is a whole different animal. It can blow up a big tire in no time at all, with PLENTY of capacity before it blows its thermal trip.downside is you have to clamp directly onto the battery.Also, for small tires, you have to be ready to turn it OFF before the tire blows up, it moves that much CFM.Clearly well made.I guess you could get a ARB that is even better, but you are spending a lot more money for it.