Don't underestimate the compactness of the regular InCase backpack. It's also very compact, but not small. For a uni student, I'd choose it over the compact version. Also, the padding of the laptop compartment is far better in the regular version.
The best thing about these backpacks is that they never look "saggy". They're rectangular, and they stay that way. The black versions look like briefcases for your back. It looks clean, not sloppy, even under load. I work at a hospital, and I purposely bought this laptop to take to work. In some ways, it looks smarter than some of the Crumpler messenger/shoulder bags that I see here (Melbourne = home of Crumpler, so lots of people have them).
If you're the type who wears their backpack sagging down (i.e. the straps are too long), then perhaps you're not the type who cares about looking "smart". If you want to look good regardless of how much, or how little, you're carrying in your bag, this is definitely the one to get.
I currently own 4 backpacks (seriously....), 2 messenger bags, and a work bag. All of them are good for one reason or another. I don't buy crap. If I need to carry my laptop, a book or two, and a complete change of clothes (plus toothbrush, etc), I'll carry my other school-sized backpack. However, for carrying a laptop, 2 textbooks, an AC adapter and accessories, and a water bottle, this is the one I'd turn to 99% of the time.