If you're not into air lines and compressors, which increase the cost, the ARB works great. I have one.
Main disadvantage: it requires you to modify the cross pin when using it with 4.56 and higher gears in a c-clip axle. Also, it's a clutch type limited slip when not locked and will eventually wear out.
I'm still considering one for the front axle though.
Mines been in about 2 years and it's still tight limited-slip wise, and the locking function still works.
Being an electrical guy, I like the electric control.
Also, make sure you follow the lube recommendations. The clutch packs don't like synthetic lube and the locker will slip on very high torque differential if you use synthetic. I had this problem and went back to conventional rear lube in mine.
Andrew is right about the ARB being time-tested though. Just make sure you do a really good job on the air lines and fittings. Most failures in the ARB are faiilure to lock and it's usually air related.
Last edited by n3elz; 01-18-2008 at 05:44 AM.