Something to consider about 120vac reefers. As stated by Nick, his draws 4.3 amps-which is admirably low. But consider that running through an inverter, like if you're dry camping. 4.3 amps at 120 volts converts to 43 amps at 12 volts (volts times amps equals watts. Watts used is always the same, the combination of amps and volts can change to achieve those watts). Considering an inverter is about 90% efficient, that means you'll be pulling about 48 amps-add to that inefficencies in the system, and you get a round figure of about 50 amps from the batteries through the inverter to run the reefer. If you do mostly power polling, that's not a problem. If you do a lot of dry camping, you'll need a big battery bank.

Compare that to the Norcold compressor type I have. It pulls 5.5 amps at 12 volts and runs about 50% of the time, for about 3 amp hours. If Nicks runs also 50% of the time, you'll be looking at 25 amp hours. Course the big difference in cost is a major consideration. $400 for the 120vac is alot less than the $1200 for a new Norcold. Good Luck, TomC