For the last two years I've had a solid gray Patagonia bookbag that I think cost $80? My brother wanted one so my parents decided to splurg and get us both one.
Couldn't find it on their site but this pic from google is exactly identical to mine, so I think it's the "Refugio" pack I have.
Anyway, I carry 3 or 4 binders and 3 or 4 college weight books to school, so this bag handles a shit ton of weight wonderfully. The straps are incredibly plush and never chafe, though the weight is obnoxious after a while. I keep calculators in the open side pockets and small goods in the small compartment in the back. Occasionally I'm bumming too hard to wear big boy shorts with pockets and keep my smartphone in a zipped compartment at the very top.
I love it. Though it doesn't have the L.L. Bean guarantee, Patagonia sure engineered this bag to do it's job. I'd recommend this bag to anyone with a boring blue/gray pallet, or who doesn't care about sexy bookbags and wants to save their shoulders. It's great having a super durable hiking bag and not worrying about getting a new one.