Hi, I have bought a fake Gucci and the leather is not a good quality and the leather will sometimes ravel, the stitching is not tight. You can tell on the inside, the authentic gucci normally have gucci symbols inside the lining. and gucci symbol on the outside, has a very good quality of leather on the straps,some of the fake/replica will not have the symbol on the outside. You will probably tell by the quality of the leather and material.
Hope this helps