To be honest I'm kind of on the fence a little bit with Sanchez. Yeah I think he's a good player, but I'm not convinced he is any sort of world superstar. If he was that great Barcelona wouldn't have kept him on the bench and then flogged him to you lot.
Like I say he's a good player, but I don't think he's a massive upgrade on what we already have, and I'd be very suprised if he had the same impact that Van Persie had. RVP was for me one of the best to ever play in the PL, but injuries held him back from having the longevity of others.
Sanchez I'm not convinced is at that level, but I hope I'm wrong.
He is definitely better than Mhkitaryan though