Personally I will always recommend full face. But if it hurts
your style, get a decent open face from Shoei, Arai, Nolan, AGV, or
similar brands. At least they provide better protection than other
cheap open face helmets.
Last month there was an accident in front of my block, the rider
was lying unconscious on the street, his helmet was also on the
street, a couple of meters away from him. Apparently it was flung
off his head during the impact. What's the point of wearing such
helmet, if it only covers your head when nothing goes wrong, but
doesn't stay put when s**t happens?