Durability on this bag has been great. I've used it steadily (2x per week) for a few years and it's just now starting to show signs of wear.
The only thing I would change on this bag would be to make it taller. I'm a short guy (5ft 7") and I don't wear huge gear, but I still have to pack everything down to get the zipper to close. I'd love it if this bag were 2-3" taller to give me more space.
Other than that - I highly recommend this bag!