I got the off brand at TSC for me. There on ok fit, little different than levis 505 but at $10 i cant complain, well other than the zipper on 2out of 3 or 4 pairs (cant remember) have pulled apart well before the jeans are worn out.
But i have ordered some second had levis on ebay (im cheap new ones are $40 on sale now!) and there have been several different textures of denim and patterns (how the thread look). So im not sure if someone got some knowck off ones and did not know it, they were just a tad different than other pairs i got and the fabric seemed thinner? But i wear them all out the same the crotch wears out and the belt loops pull off, like the cotton rots out or something. In college i did not have as much trouble with them lasting, but maybe it was cause i sat around more? That or i was 25lbs lighter mostly and there wasnt as much streess in them in the thinghs and waist?