There are only two directly-comparable chassis that I know of, and those are the Tamiya CC-01 and the ECX Rampage. The CMX/CFX is better than both.
The CMX has a slightly better center-of-gravity, but the CFX has a more realistic layout, and also allows more space for a decorated interior if you're into that sort of thing.
I had a Unimog body on my CC-01. I much prefer the CMX/CFX chassis vs. the CC-01.