There are a lot of ifs there. I don't know what's the most likely thing to break down on a Terrano in the middle of nowhere, all alone on a mountain. But if I was to bring a spare part to cover the top 20 things that are more likely to break down than a hub and cripple the journey, then I would need a trailer load, one of those african safari trip jungle set ups.
If I was to go off-roading regularly as a hobby or out of necessity and be venturing solo into a get home or your dead/dying situation, then I wouldn't use a Terrano, there are too many weak parts, it's a cheaply constructed jeep. I would want something that was built stronger. The Terrano is more of a jeeplet.
Nevertheless, the Terrano hub in my experience is more reliable than other essential parts.
The worst (non self inflicted) that happened with my Terrano on off-roading on various long holiday/sight seeing trips, was a broken cv joint, puncture on 2 good tyres within an hour, starting motor and alternator stopped working, water pump gasket leaked profusely, fuel line leaked, but the hub was grand
If you were worried about the durable Warn manual hub breaking, then bring the fixed hub spare, it doesn't take space and it's dead easy to replace should the need happen.
