An Efoy depending on model (mine is a 1600, now discontinued) can run you 4K, good for 3000 operating hours. Newer Comfort models may have 4500 hours in them. For me a 10 liter M-10 container of fuel lasts about 200 hours, clock time. Cost online is $59 plus shipping/Hazmat fee of $30. All that works out for my setup to about $1.75 per clock operating hour for my 60 watt at 12 VDC unit.
Unit is totally silent outside the camper, and less noisy than the refer inside. Genset restrictions don't apply if you're in a national park campground, and if you're on a ferry with propane secured for a couple of days, your beer is still cold when you arrive, batteries still fully charged. Gotta pick your priorities :-)
duncan