I've had this bag for about a month and LOVE it. I have a 15.4" hp laptop and though it's snug, it definitely fits. I am a law student and find that it fits my laptop and 2 case books quite tight, but is a wonderful bag to protect my items and get from my apartment to the library to class and back.
The waterproof material is brilliant! It works perfectly and is a very important feature for a laptop bag [especially in stormy New England].
The multiple pockets are wonderful, I really enjoy the handle and the padded strap. It is a perfect bag for what I need. Highly suggest it!