I bought a pair of 518's from Amazon and when I got them, they looked so cheap and the hemming was horrible.  According to levi.com, amazon.com is NOT an authorized seller of Levi's jeans, which means you are apt to get a fake. It's not hard to tell. The fabric is a good place to start, and the fit. I sent them back and of course, I got a refund, but I just wanted people to know they may not be getting what they think they paid for.