I just got done installing my new (to me) Rock Block in my samurai and I must say....WOW!!!
I thought the Rock Lobster T-Case and 4.62 Diffs were cool...lol.  I now have a 2hi, 2lo option, and 4-4wd options
Can't waite for a Bedford Boys trail run to try this thing out!  OH...and big kudos to Brent at T.T. for helping me with a couple of questions I had during the install!

UPDATE:  OK..been driving the samurai around most of the weekend, and haven't really had any major vibs. comming from the R.B.  I know several people have asked me about this.  
They are worse at highway speeds, but I have noticed that you can play around with the block and find the "sweet spot" where the d-shaft lines up correctly.
But, honestly, the vibs. comming off of my tires are just as bad.

sounds like a sweet setup ...

what's your low-low gear ratio?

climbed a vertical wall yet  

over all is 125.53
I have an retaining wall by my house I've been eyeballing for the last two days...lol