We loved our Calmini 2" lift. Ran it for 20,000 miles without problems. (It has since then been modified with jeep TJ springs and some custom springs up front, longer shocks, etc...)
We like the fact that we could add on and modify it to the monster it is today. Couldn't do that with the R.R. kit.
Can't think of any CONS right now. I'll post again when I can think of one.
~Nate