Lots of folks have reported her 20+mpg, typical is in the 16-18 range. So many variables, if you drive like you don't have brakes, it helps a bit.
I'm sure the poster has no comparison between V8 and V6 diesel. I hear the diesel performs better, but at a $5000 premium entry fee it better. Those that want 0-60 performance go with the WK2 STR8 model. It pretty much blew away competitors from Porsche and Mercedes that cost $20,000 more. You can get a faster 0-60 SUV if you want to spend $110,000+, however. There was a link to the review posted here maybe a month ago.
Lots of performance discussion in a number of threads here (as well as mpg threads). It should be easy to find them with a little search.
Current: 2011 Grand Cherokee Overland V8, 2009 Liberty Rocky Mt V6
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