Ive used all types and brands of packs - Gregory, Mountain Hardwear, Osprey, Arcteryx, and TNF....and so far, Osprey takes the cake! Ive had this pack for four years now and it is still in amazing shape. I first bought it before going to a search and rescue school. At the school I used it solidly for 9 months which included carrying roughly 40-50 pounds for periods of up to 60 miles...in one day!! NEVER had any hot spots or rubbing in my back or shoulders from the pack...it is amazingly comfortable!!
And as far as durability goes, as I said ive had it for four+ years and it is still going strong...even after having it fall off the back of my motorcycle at 50mph...this thing is BOMBER!!!