i have an Iceco JP30. used it at the bantam festival, worked great.
during the day i plug the fridge into the 12v port in the rear of the jeep. at night i have a U1 size agm lawnmower battery ($125)in a small plastic battery box ($15) and plug the JP30 into that. it ran it fine overnight.
then the lawnmower battery has a 4amp walmart charger attached ($45). i plug that into the 120v outlet on the rubicon center console during the day and it gets recharged.
I have an IceCo VL45. Works great. Had it on 2 trips so far. Leave it plugged in 24/7 to vehicle. Never used enough power to trip low voltage protection. Used in JLUR and also in a 14 Durango with original battery. I have it set at 34* or 36*. When I first got it I left it at 0* for a week to make sure it worked good, which it did.
Specs say mine uses 42 watts while running.
P.S. Amazon is $530 right now. I got mine last Nov. Listed for $490 plus some sale for $98 off. I paid $413 with tax. So there is deals to be had just have to be patient.
P.S.S. Oh and its 100% better than any Yeti, RTic, or whatever brand cooler. Ive had them all.