When the current unit goes there are basically three or four sections
The cooling unit. This is the "Major" part and if it fails I'd go with an Amish Built unit to replace it
Elecronics (2 sub assemblies) easily replaced. though a common issue is bad connecrtions on the connecting cables I have seen that twice (once personally) Cost to fix (Unplug and replug several timnes both ends) ZERO!!!!
Burner and gas control valve
Electric heat element.
Now many have talked about the "Dangers" of an absorption heat unit (Slight fire danger) Hailer just recalled some of their Refrigerators (Residential type) Seems they have had reports of them CATCHING FIRE.. Yup.. A serious case of replacing the frying pan with ... Another frying pan.
There is a slight size advantage with residential and they are more efficient on 120v (But do not run at all on propane).
Both Dometic and norcold made if they do not make all electric HIGH EFFIENCY units. about 30 to 40 watts running. door closed. add about 50% when you open the door (The light draws that much power).