I had an ARB in my 4th Gen and now I have the Toyota E-locker in my 5th Gen.

The build process for the ARB was a PITA (not ARB's fault) and I ended up learning a lot because the shop I was paying fell short in knowledge and experience. ARB USA folks were wonderful and fully supported me until the locker was working correctly. I would say change the diff oil often because any tiny bits of metal end up damaging the rubber air seals in the locker and generate air leaks. It gets expensive to have to disassemble things multiple times. Route the air line well and there should never be any issues with breakage. I hated how the ARB would "burp" oil back up that line. There are supposed to be some cures for that.

The Toyota e-locker is great too. I've tried to actuate it often so as to wear things in a little and it seems to be smooth and quick when needed. On my recent trip through Death Valley there was one (insane to me) hill climb that just kept getting worse as I ascended. So I pushed the locker button, the elocker engaged quickly and my ascent improved noticeably (so did my confidence in the Toyota locker).

The e-locker's engagement collar/sleeve has fairly fine splines so it does not take much wheel rotation (if any is needed) for it to be able to engage quickly. The Eaton has different mechanics.

So pick whichever design (and costs) to meet your driving needs and then get out and wheel it.