I fully agree about taking your gear with you if you can. To be right for you, a pack must do two things: it must be able to handle the weight, and it must work with your gear.

I've rejected some packs simply because my gear didn't load into it conveniently. The Gregory Z55 (and its ancestor, the G Pack) doesn't have side pockets; it has a "shove-it" pocket that runs all the way around 3 sides - which meant I had no place for my water bottle, because it kept sliding around. The orginal Osprey Atmos 50 had a curved shape that was so radical that I couldn't put my tent poles inside the pack. There was another pack whose lid was large, but divided into 3 compartments - and none was large enough for a map.

Definitely, take your own gear with you.