As you can see, there is no definitive answer. Generally, an absorption unit is good for a period of months of use, rather than a measurement of years.
There may be some difference in mfgr. or by which power source used, but to me, its moot.
Absorption cooling systems have inherant difficulties that will lead to a failure someday. Near as I can tell, it's about cumulative use. A FT user, as I once was, may expect 10 years, a seasonal 20, a weekender,the rig will rot out and fall into dust before the fridge gives out.
Don't worry yourselves about it failing suddenly. Very rarely do absorption cooling systems fail suddenly. if it does, its likely a control problem.
Cooling loss is ansidious and gradual with an old worn out fridge.
Max