Grinwrote a review of Arc'teryx Axios 25 Daypack - 1648cu in on April 25, 2012
This has been both my laptop and general travel bag for the past year or so and has done pretty well. My biggest complaints are the carry handle having broken after only having the bag for a short time, (it snapped apart where it attaches to the bag on one side) I was in the middle of moving to the other side of the world and didn't have time to send it back, so I just stiched it up with some spectra thread and it hasn't been a problem since, though I tend to avoid using it with a heavy pack now. The plastic sheet that makes it semi-rigid has cracked about 5 inches from the top, though it's hard to blame anything other than it being compressed in my locker in less-than-ideal positions.
The fit is spot on whether I use the hip straps or not and they tuck into the pack when not in use. The heaviest load it's had to put up with was probably around 25lbs and it wasn't uncomfortable, despite my lack of natural padding at 5'9", 140lbs. The mesh back does an admirable job of both padding and keeping your back from sweating too much.
In terms of a computer bag, there's no padding on the bottom, so dropping your bag is about the same as dropping your laptop, be gentle. The Hydration sleeve fits slimmer 15" notebooks, such as the Macbook Pro like a glove, but thicker than that and they'll have to sit outside the sleeve.
Compartment layout is pretty good, and the brightly colored fabric used in the lining makes it easier to see inside the pack. The one main compartment is fairly spacious and compresses well when empty. The smaller outer compartment is a bit awkward in shape for holding much other than clothing. The smaller outer pocket and the one inside the main compartment are lifesavers for keeping small items handy, and can hold quite a bit if stuffed tight. The side mesh pockets only manage to hold things that are also strapped in with one of the compression straps and the hip-belt mesh pockets are pretty much useless.
The ripstop fabric shows every bit of dust and dirt it touches (I have the black) though it cleans up well with a damp cloth. I believe I have the previous season version, as the ripstop pattern is not nearly as pronounced as in the pictures, so I can't speak on the current model and any changes that have been made.
All in all, the bag has held up fairly well to all the abuse I've put it through, but I was hoping for greater durability from Arc'teryx.