For years i hace succesfully used the ARB and love it! it does suck amps, depending how far below ambient temp u want to go... get an aux battery to power the fridge. ARB units are re-badged Engels. Get the engle and needing ice is a thing of the past-- altho a bag of ice will stay frozen in ur fridge and i use it as a way to keep down constant amp draw and to have drink ice for the camp-fire cocktails.
oh, and hard wire the connections-- i use a trailer style plug to connect it to power-- the supplied 'lighter plug' usually fails the 3rd of 4th hour of use-- just too much juice to pull thru t hat type of connection. i know the hard way-- mine melted and shorted out. bad day, but i had some spare wire to jimmy rig up a battery connection.
if u pre-freeze ur meats, etc before you leave, it will last much longer.
mb