Ohhhhhhh .... you'll open a can of worms on this one old mate!!! lmao

They're both great, and it really comes down to personal preference as to whether you want to be able to turn it on and off, or set and forget.

The auto lockers I've seen in action are awesome and always there when you need them, and are probably less than half the price fitted. That said, I have an ARB air compressor hooked up to a TJM ProLocker (air) and couldn't be happier ...

No doubt you should get plenty of response on this one mate and good luck whichever way you go.