In reply to tobias_sturm:
I have one of the new Deuter Guide bags, the back padding is fine for hiking in my experience. I only really get a sweaty back when I have it on for MTB (also a pretty decent bag for that imo) but I've yet to find a bag that doesn't have that issue.
In terms of climbing use, I climbed Pillar the other week with it full of camping gear. Got up the route with little issue from the bag. It even made it out of the chimney pitch in one piece, same can't be said for my water bottle!