My neighbor as a Nitro with the factory 20s and gets mid to low 20 mpg. as for the 5 speed auto my guess is they are limited due to the liberty using the nitro platform and not have enough room for the 5 speeds. But thanks just a guess.
check here.
http://www.jeepforum.com/forum/f98/
I like the looks of it but if I were to be buying a new smaller 4x4 I would look at the Nitro/Liberty. Little bigger and v6 power.
I like it still think they would look better on my Jeep but I still like it. Wonder what it would look like with a set of golden eagle Ravines on it.
http://upload.wikimedia.org/wikipedia/commons/f/f0/2006_Jeep_Golden_Eagle.JPG