The only thing I DON'T recommend is the OX. It's a PITA to install, and a PITA to keep adjusted. They scream up and down that it's installation error every time, but if you saw all the BS you have to do with the cable when you install it, you would never do it.
I think the ARB is the hands down best selectable out there. But they are also the most expensive, and you still need a compressor.
The ECTED and the E-locker are a little different.
As far as I can tell searching the net (without tearing one apart), the ECTED uses magnets to force balls into the LS clutch packs. Since it's not forcing a collar into splines I would assume that at some torque limit it allows slipping. I would say it's a great product for up to 35" tires, and Auburn has a great rep for replacing any problems.
The E-Locker forces ball bearings into pins that lock the side gears to make a spool. It uses magnets, the ARB uses air. Kelly, I think with the size of tire you have, and your HP it would be a choice between these two.