Luke,
No doubt a 500d or better yet 1000d Cordura pack will out wear the KU, but that is one of the trade offs to loose so much weight. I don't think the KU are for everybody and Patrick must feel the same way as they aren't replacing any of the heavier packs.
I have owned a couple Longhunters, both G1 & G2 and a Siwash and they were great packs and carried heavy weight very well, especially the G2. But every time I would pick it up empty, I wonder what was in it. The KU's are like a day pack with the capability to carry big loads.
I don't think you are alone in wanting a KU 6500-7500 and I wound't be suprised if we see one in the future. For most of my trips anymore, I can get by with the 5200, the rest of the trips I can add a pod and a couple long pockets and be OK, but there are some areas and trips where a bigger pack is really necessary.
I hope I wear out my KU, 'cause I'm pretty sure that would take one heck of a lot of trips over quit a few years and I wouldn't mind getting out that much.
