The 2008-2009 EX35's have the older navigation system that isnt as advanced as the 2010+. it was again updated in 2013 or 2014, and while it is functionally identical to the older ones, it has updated internal hardware that makes things like the bluetooth more reliable.
The 2011's got the 7 speed and the white gauge cluster, and in 2013 they went to the Vq37VHR 3.7L that bumped the power up some 25hp. 2016 they stretched the chassis out and it has significantly more legroom
i would say get as new of a model year as you can afford.