We have been through 2 sets of Michelin LTX A/S and now are on our first set of the LTX AT 2 on our '04. 5. Both LTX A/S sets have gone close to 100K and I'd have to check for sure, but I think the AT 2's are in the ~40K range now. That truck sees a lot of highway use, tows quite a bit, and is used off road nearly daily. All and all, the tires are worked hard. Now, I am doubtful that the AT 2's will make it anywhere near that 100K range. But they are offering much better traction off road and in the snow. I can't say anything negative about the LTX AT 2's other than they are becoming a bit noisy as they get some wear on them.
Just a little food for thought, I have had a great experience experience with the new Firestone tires on one of our Chevy work trucks and decided to put a set on my '07 Ram. Having the Firestone Transforce AT's on the '07 and the Michelin LTX AT 2's on the '04. 5, gives me an excellent chance for comparison. So far, both brands have been excellent and I can't really tell any major difference in performance, traction, wear, etc. The Firestones are considerably less expensive than the Michelins, making me seriously consider running them on everything eventually as long as no major factor comes up.