The Osprey Porter 46, perhaps? Osprey backs up their products, and the build quality is excellent. It also has a great, functional hip belt, and both the hip belt and the backpack straps can be securely hidden away should you ever need to check the pack.
You can get the Osprey Porter 46 from eBags, so you could always order a Mother Load TS Weekender and a Porter 46, check them out side-by-side, and keep the one you like best and return the other.