Here is a review from someone in New Zealand:
There has been alot of interest in the chinese arb clone air lockers now available. Alot of people have been waiting for someone to test one out first before trying one. As an experiment I fitted one to my Canterbury club truck 4-5 months ago and have done about a dozen tracks using this rear locker in that time. Am now happy to comment on the locker.
Found the unit easy to install and the compressor, though a little noisy, does the trick very well. Have it mounted under driver seat and a bit of sound insulation material will solve that issue.
Being selectable I only use the locker when needed, but have given it a fairly tough workout on a few rugged bits of country. Have also run it for one or two extended periods - about half hour or so.
I have found the locker to be 100% reliable. In the past have used aussie lokkas which I like, but this chinese air locker works very well and at its cheap price it creates a new selectable option for club 4wd trucks.
Have not done heavy winch challenge or competition work with it, but for club trucks and tracks I'd say it is a good option. I know of another truck with one of these units installed and it is working well also.
I think the advice to strip the locker and check and debur components first if possible is very sensible, though I didn't do this on mine.
I should mention there is a guy in chch who has imported a few of them for isuzu owners and is selling them at about cost - round 1100 I think - inclusive of compressor. He also fits them into your isuzu diffhead free, a precision job which can otherwise cost an extra $350. An EXTREMELY good deal, for isuzus only.
In all, this chinese air locker hasn't missed a beat in my club truck which is all you can ask. Just one locker tested, but from my experience I give it a thumbs up!