Depends on what you want, they all break down at some point but I've found that with preventative maintenance they are reliable but, unlike euroboxes they do like regular attention and a few sheckles here and there. I'm about to re'do the boot floor after 6yrs as I seam welded the new/old one to the side panels which makes it a ball ache to remove and as the side panels have gone at the joint to the rear quarter panels I figured that it all might as well come out, wheel arch tubs an all, I've got loads of 1.5mm sheet and I am thinking I will just strip out the rear quarters too and weld on some stiffening strips to stop it drumming and jobs a good un, well, sort of.
One thing I will say is that all too often these old trucks, by the time we get hold of them are fairly well wore up and rotten, bought and run on the cheap until they can't get through an MOT and then we not only need to weld up all the rot but fix all the other bits that wore up before the rot got too bad to pass the test. That usually means suspension bushes, leaking gearbox and transfer box seals, axle seals and bearings, brake lines, pads and rotors. In all honesty, if you were to sit there and work out all the costings for parts alone then factor in the amount of time, blood, sweat and tears there is no chance in hell anyone with any remote sense of sanity would ever dream of doing what we do every weekend, just for a hobby.