I have a G19 with SDB*** serial and a G17 with TBD*** serial. Originally, the G19 would hit me in the face with brass at least two or three times per mag. It seems to have gotten better. However, the G17 originally was fine, but will occasionally hit me in the face (maybe one piece of brass out of 50-100 rounds).
Glock really needs to fix this problem. It not only causes the shooter to flinch, but it burns my face. It's especially bad for new shooters because they might become afraid of shooting in fear of potentially getting brass in the face.