I have had them for a week, so I cannot comment on durability yet. However, they seem better quality than Levi's, and I do not find them less comfortable, and they cost less.
One note, some other reviewers lamented that they were longish relatively to the stated measure. I found that not to be the case (at least as compared, once again, to Levi's). I bought 32W 32L, and it appears to be a "true" 32L, in fact, I would probably have been better served by buying the 34L, just as I do with the 501 (to be clear, it's not that the 32 is short, just that I expected to be longer given that other people lamented that fact).