We were super keen on a new Grand Cherokee but decided against it in the end. They're a great looking car, but i've got one friend with a WK2 and one friend with a Wrangler, and both have talked about warranty issues and trouble getting parts. I haven't heard anything in the past 8 months or so, but back then they indicated there was a shortage of spare parts in Australia. That said, both of them were given a car to drive while theirs was out of action.
We've also got two friends who work for car dealers. One is a buyer for Q Ford, the other does fleet sales for Zupps. They both warned us to stay away from Jeep. I suppose there'll always be someone ready to say bad things about any make or model, and it's a shame to hear the negative feedback because i had my heart set on a Trailhawk, but i'd rather be disappointed about not getting a car than disappointed about getting a lemon.
Good luck with whatever you get.
Mike