All the old brands are real. We Beijingers buy time-honored brands and sometimes go there. You know where you put your things and why. There are also many shops around Qianmen East Street and Food Street, as well as many old shops including Dashilan. Most of them are rented by outsiders. If it's the so-called genuine goods sold in those places, it's probably fake. If you find that it is really an old brand, you can go to them. A century-old shop won't smash its own signboard for that petty profit.