I had a 3 way but never used the propane option. Unless they are just about perfectly level, the lines can turn solid. Not frozen...solid. As in forever. Also they are quite energy hungry.
There are some brand new units that employ a new type of 12v compressor that I have been reading up on that look very promising. Very low energy consumption and unlike the funky solid state toys can freeze as well as handle refrigeration. They recently came out with a dual zone model that combines fridge & freezer. All are the chest type which also conserves energy by not dumping all the cold out every time the door is opened.
Here is the one I am considering...will fit nicely on slides under a cabinet/sink area.
PS...Dometic now has similar units as well.