For what it's worth, it depends on where in Guangzhou you go. The city, like almost all cities in China, has expanded dramatically and the western parts, away from the train station and the "old" Mao-era section, is safe. We spent a few weeks there this past January and the newer areas are fine.

To the OP, if you want counterfeits, take the train from Kowloon to the border, Luohu. There's a huge multi-story market just across from the train station that has all the counterfeits you could want.