australopithecus: One small comment. I've toted daypacks about (hiking/cycling) for decades and I get the impression that the camera-gear bag manufacturers pay too little attention to the straps, hip-belts and especially the airflow between one's back and the bag. They could all learn from Deuter who make world-class day-packs. Deuter's "Air-Flow" system is ideal.
Don't know about this one but I use Kata MultiPro-120 daily. I have 2 LowePro backpacks in different sizes but when it comes to straps Kata beats them hands down.