I have a Deuter City Cross backpack which I've reviewed
here. I regularly carry a 15" Dell laptop in it. I don't know if a 17" laptop would fit. If you measure your laptop, the Deuter web site should be able to help you there.
Overall, it's a good backpack and does what I need it to do. The laptop is in its own little pocket, and the rest of the main part of the backpack is big enough to carry clothes, shoes, toiletries etc. It's comfortable to wear unless I'm carrying a very heavy load. My most common complaint about it, however, is that my view of what's behind me is somewhat limited. Shoulder checks are difficult to do effectively.
After 12 months of commuting with it, I'm ready to move to panniers. This is for two reasons - one, I can do visibility checks much more readily, and two, I can carry more stuff. That said, if you can confidently carry the weight of the backpack with laptop etc, then go for it. It's worked for me for the last twelve months, no reason it couldn't work for you too.
Max