I need a good, durable pack for a unique situation. I'm going to be doing mission work in remote areas in the mountains of Peru. Most of the work will be between 12,000' and 16,000' in rough conditions. I love the ultralight aspect and do extended hikes here with a weight in the 30 lb. range. In Peru though I will need additional room and caring capacity, at times, for books, medical supplies and various other supplies and will need to be able to handle 45 lb. – 50 lb. and be able to compact down well to the lighter loads. What would you recommend?
I've pretty much narrowed it down to the Osprey Aether 70 or the new GoLite Quest. I've tried the Aether on and love it. It's just hard for me to start with a pack that heavy, but good suspension and frame are more important. I've also tried Deuter but don't really like the way they fit me. The load feels to far off my back compared to the Aether. The GoLite looks very interesting but I know so little about the new model and am not sure if it's even capable of what I'm looking for. There's no reviews out there on the new version and all the pictures are from the front. Anybody have any experience with them. How do the perform with the loads I'm looking at? The price is so good on the Quests right now.
Any thoughts, ideas? Am I missing any other good pack in this category? Thanks.

