I understand thst ARB lickers are suppose to be “awesome” and superior, but I have observed frequent, and often repetitive, fails of the ARBs on wheeling outings so I went with Eaton e-locker (front and rear). I have had no issues whatsoever, and tgey have always engaged, except I had a brief spell where my front locker was acting a little finicky, and I found the relay switch badly corroded from frequent engine washes and no dielectric grease placed on install.
Way more things to go wrong with air-lockers.. compressor, hoses, fittings.. Ever try fixing a blown hose on the trail?
Far less to go wrong with an elocker..
The only advantage of an air locker that I can think of, is that an air-locker engages immediatly where an elocker takes a second or so to 'ramp in' ..
..I have elockers front/rear..
I've always run ARB air lockers on my MischiefMaker and I often wheel with people who have Eatons. I went with ARBs for 2 main reasons...according to most of the people I've spoken with 1) ARBs simply don't break and 2) They engage immediately instead of needing roughly 270 degrees of rotation to engage...which could make a huge difference depending on how/what you like to wheel.
Honestly, I've seen problems on both sides. I've had a line blow on the trail and running a new line took maybe 30 min. The only other ARB problem I've had first-hand experience with is a bad solenoid, which wouldn't have taken too long to fix IF the Jeeper had a spare on hand.
My very limited experience with E-lockers issues has been worse, AND I believe it to be more of an unusual case. On our first trip to Rausch with the trailer a Jeeper with a Rubi had a malfunction on his front e-locker and it wouldn't disengage. We first had to troubleshoot the issue as an electrical problem (disconnect battery, etc...), we then then took the diff cover off to check for mechanical issues -- we never actually got it figured out on the trail or at the hotel parking lot. Finally, we ended up towing him home and he was nice enough to fill the tank of our 1500.
I think the main thing to consider is how you wheel. If you are going to be rock crawling and reversing to adjust lines then factoring in the 270 degrees of rotation (that can be quite bit of room with 37'+ tires) required for an e-locker might be less than ideal in comparison to the near instant lock of the ARB.
That has been my experience to date. Both have issues and you can never really predict what will happen on the trail, but IMO carrying line repair kits, spare air lines and a spare solenoid seems worthwhile...