I tossed it around a while in my head and I went with an ARB. It was more $$, but it was new. And like the kid said, it's stronger than anything else out there.
I didn't wan't an auto (lunchbox) locker back there because I drive in snow a lot and wanted to control being open or locked.
I didn't have the means to modify my axle housing for an elocker 3rd swap so that was out. And don't forget you still have to wire it all up.
I didn't want to pay $800 or so for a complete axle and have to sell my original axle later. I didn't have the room for it at the time and I didn't want to take a chance with someone's used axle (could have issues like it's bent, leaking, axle seals bad, etc..).
So in the end the ARB was the best choice for me. Plus you'll have on board air if you get the bigger compressor. A rear ARB installed w/ compressor will cost you about $13-1500 (depending on what compressor you go with). I went with the ~$150 small compressor and it works great to run both my lockers. I also chose the small one because I like the idea of having a separate, dedicated compressor for tires and stuff. I think it's best to have the ARB compressor just run the ARB(s) so it doesn't wear out fast.
I did my gears at the same time to save on labor and kill 2 birds with 1 stone. I'd recommend doing the same if you plan to lift or run 33s or bigger.
BTW, you do have to make a small modification to the axle housing to run an ARB - you have to drill a hole for the air line, but it's no big deal.
