This bag is big, roomy, sturdy and waterproof which is all great! The only problem, is if you wear the bag with just a tshirt, and not much in the bag, then the spiky feet at the bottom of the bag bends around and scratches up your back which can get quite painful! When the bag has alot in the main compartment then this issue doesnt happen, but its worth keeping in mind if, like me, you use it for a festival or somewhere hot where you have a thin layer on.
I emailed MAgma about this and they said they didnt test it without much in the bag which i thought was pretty useless lol.
Other than that its a great bag!