Get the Keepall. It would be roomier. The Carryall is more like a purse. If you need the strap, consider a Bandouliere version. I have a regular 45 which I attach the strap to, but since you want to use it everyday, I wouldn't recommend it. Damier canvas and leather might better with stand carrying, but I don't know about the scratching of the leather. Don't get it too big, or it will be too heavy to manage. Probably stick with a 45 or 50, because of books, laptop. etc. Also, if you ever have to moosh it a little to fit an overhead compartment on a plane, it seems it would do it more easily than the Carryall.