Mine leaked out and broke in half after day, ~ 250 miles in desert. Not that it really means anything. My companion on Land Cruiser also had OMEs and didn't have any problems. (althouth their shock layout is different). Monty shocks do have to work harder since they are positioned at steep angle so have to be valved harder (providing more resistance at shorter distance) meaning fluid is exposed to higher pressures and higher speeds traveling through valves, meaning higher oil temperature and higher probability of foaming. Aslo being double walled OME Nitrocharger will have even more problem dessipating the heat as compared to mono-tube.
High pressure mono-tube shocks should generally fare better in those conditions.
Although twin-tube shocks have couple advantages:
a) if external shell gets damaged shock will continue operate normally unlike mono-tube where piston may get
jammed.
b) they generally have longer travel since they don't need extra space at the bottom for high pressure gas chamber like mono-tube shocks do (unless of course you go with fancier external reservoir high pressure shocks)
None the less I'm sure OMEs are good shocks, mine were fairly old too.
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