Let's be real here. Gyan and Sess are good players, but Gervinho is top quality and Hazard is an incredible player. Sow wouldn't get anywhere near the same kind of quality delivery at Sunderland or even Newcastle. Plus, this is a much tougher league.
Other clubs seem to realise this too. This guy has scored 25 goals in 36 apps. He's one of the most prolific goalscorers in Europe at the moment, yet no one seems to be that interested, do they? With that sort of record you would expect some top clubs to be all over him, but so far there isn't much to go by. In fact, people seem to be fighting over Gervinho and Hazard much more than Sow.