I agree for part of what you are saying except price for the OP particular situation. They have a functional 12v system and camp on the beach in full sun. The dorm fridge will run at least 30-40 minutes of every hour as the insulation is designed for an air conditioned room thus drawing large amps. Sure with a good inverter that pulls very little amps but the fridge will drain a group 24 past the 40 percent mark in less than 8 hours with solar it could be maintained barely during the afternoon but the 12 hours from 6-6 will drain a group 24 past the point of no return. Not to mention the longevity of the dorm fridge is questionable if it is knocked over or laid on its side it may not work again. Personal experience with this. With a Danfos type fridge/freezer it has almost twice the insulation virtually impossible to knock over and the biggest point it will not run more than 15 minutes every hour out of direct sunlight. So it will not drain a group 24 past 12.1 in any 12 hour period. There are many people like me that tried the dorm fridge route just to end up with a good Danfos 12/24/110/240v compressor fridge that will last for years. I have a 15 year old ARB and have had it plugged in to house current the whole time except when I throw it in the Jeep or truck. Never worry about ice or wet food or the worst case knocking it over as it will start up even after you roll your Jeep on the trail. And the contents will stay put because the lid securely latches.