I'm running Ox lockers front and rear and they've been working great. I love having the shifters and they lock smoothly. My rig doesn't see nearly as many miles as most do so I'm not sure what to expect for long term reliability.
I will say that the instructions are VERY clear that the cable routing is important to ensure that they are not damaged from heat/exhaust, maybe this is why so many people have adjustment and shifting problems.
If I were buying lockers again I would probably go with a different brand for the hell of it, My used axle had the OX already when I bought i so I wanted the front and rear to match.