It looks as though I am in the minority here, and this is based just on looks but I have to say mine is the 5th gen.
I'm not much of a car guy in the first place, and there are not a lot of cars out there on the road that catch my eye. The first car I said I had to have was the Durango when it first came out in 98. In 2005 I was able to buy a used 98 Dodge Durango with I think it was 156k miles on it. I loved it. But as the body styles for the Durango changed, I got more and more disappointed as I did not like the newer styles. I thought there would never be another SUV with a style I liked. Then in 2011 or 12 I was flipping through a magazine and saw a pic of the next vehicle I had to have. (Keep in mind I never payed attention to Toyota, much less the 4Runner before.)