Deuter makes a great pack. I briefly used an ACT Lite and ACT Zero series pack (I want to say one was a 50+10 and the other a 60+10, but I can't really remember.) They are really nice packs, with superb adjustable suspensions. They carried really well, and both are now on friends' backs, both are delighted with the pack.

The only reason I am not still using one is that it's simply overkill for the load I typically carry (about 16 - 18 pounds of food, water, and gear other than the pack.) There was a bit too much volume in the 50, and the suspension was far more than I needed. So, I found a pack (Gregory Savant 48) that was half a pound lighter and still sufficient for my needs.