I bought this for use in my commute to work. I split time between two offices and need to move my laptop and files comfortably and securely, this backpack fits the bill. Lots of room, and understated enough to bring into a professional environment. I looked at similar bags from North Face and Mountain Hard Wear, and for my needs, the Underground was the first choice hands down. My only gripe is that the loop strap at the top of the bag is weak and was one stitch away from becoming detached after only three weeks. I'm swapping it out for a replacement, so we'll see if it was defective or a design flaw.
Strap tore after only 4 days of use. I expected more durability at this price. Bag is also quite small.
Pro: Lightweight with handy pockets
Con: Poor construction & small volume