Later models will no doubt have some improvements. How much are you willing to pay for those improvements? Any improvement; mechanical, ergonomical, interior, exterior - will obviously cost more. This vehicle is a truck with plenty of "giddy-up" for the street and awesome off-road performance. And, in it's current configuration, damn fine at under 30K.
Personally, the '06 is more than enough for me and will be my rig for many more adventurous miles. My 2cents.
