Dustin,
Like you I wanted the LSD/ARB combo in mine. Also like you I only had cash for one at the time. I did the Calmini LSD first, only because Calmini had it in stock with no idea when they would get more. If Calmini's supply were more stable I would have gotten the rear locker first. Another option that may be attractive for you is to put the Calmini LSD in the front and add an extra disk to the rear LSD like wheelit and TK1 have done. Adding the extra disk is something that can be done in the driveway to save some bucks.

As to all of Brents other comments. I'd guess it's my driving. I'm able to tackle tougher obstacles and I'm breaking more parts in the process. I would definitely invest in the Calmini steering with any kind of traction device in the front end. Or try the TK1 mod on the centerlink. I went from one centerlink in 6 months to 1 a weekend with only the front LSD. The stock steering can't hold up with the front axle doing most of the work if the rear is spinning.

I broke one motor mount with the LSD only and one with both the LSD and locker. The mounts are a weak point, so it wouldn't matter which end is locked, the torque has to go somewhere. Spinning tires act as a safety release and unload the drivetrain. With lockers the mount has to hold the torque of the engine. In each case I could have winched myself and prevented the damage, but it's more fun finding the limits. However, Steve Kramer has said motor mounts are on Calmini to do list.

I've also replaced the passenger side front axle shaft. It was getting loose on the inner tripod joint. After I got it apart it looked like the tracks the tripod slides in had been notched. This was right before I installed the locker.

The broken tooth on the ring gear happened sometime after the LSD was installed, but I don't have any idea when, I only found it a couple nights ago when I did my first fluid change on that diff. It could have been improper installation, me pushing the truck too hard or due to the violence of the LSD slipping.

As to my impressions of the Calmini LSD. It's basically a spool that lets go every now and then. It's not at all smooth like the stock rear LSD. When it slips in my truck it sounds like something has broken. The thing bangs. It's gradually getting a little smoother as it wears, Steve Kramer warned me of the behavior when I bought it and at goneMOAB this year he told me to call him if it ever quit making noise. This is really only an issue at low speed tight turns with power. I've never noticed it blasting down dirt roads in 4wd or driving in deep snow on the street. But do a U-turn with the steering against a stop and you will feel it.

On the plus side I have yet to see only one front tire spin. It seems to get tighter with load on it. As it is now I only use the rear locker when I think I need the extra traction, most of the time it is off. Between the front LSD and rear locker, the LSD made the biggest improvement in my truck. It's probably because it was first, but locking the second axle wasn't nearly as noticeable an improvement as locking the first.

Lastly it's very tough to steer at a standstill, much worse than the binding inherent to a part time 4x4. Usually I have to let it roll a little to unload the drivetrain and really crank on the wheel to pop the LSD loose.