"I bought the older version (4200 vs the new one at 3750) of this pack this summer, and I've been very pleased with it so far. It carries loads up to 30 lbs without any trouble. I love the number of adjustments you can make to help the pack fit properly. Unlike most packs, it does not have a shoulder "yoke"; the Chimera's shoulder straps adjust independently, allowing for a more comfortable and personalized fit. Although the straps, both hip and shoulder, are not as padded as some, I find them much more comfortable than Kelty's super-padded shoulder straps and hipbelt.
The only nitpick I have is about the volume. The Chimera is supposedly a 4200 ci pack, but it is smaller than my Kelty Tornado 4000 and my EMS 3000. I read a review that stated that the volume was more like 3200 ci, which is probably accurate. It holds all my gear, though, so it is not a problem for me.
I'd recommend this pack for women who find other pack's shoulder straps to be to widely-spaced. One of the Chimera's many adjustments allows you to move the shoulder straps closer together or farther apart, so you get sore shoulders or collarbones.
All around, this is a great pack, and I'd buy it again in a heartbeat."