I think the resentment with many comes from his going AWOL in trying to force a move away, which at 17, fucking stinks. But fair play to him for going abroad, it's clearly worked out for him.
I do think he's being massively overrated at the moment, look at his goals this week. 3 tap ins from heavy counter attacks, 2 or 3 against one. Dortmund system is so good for a winger, as they get so many chances to break in numbers and bag easy goals + assists.
I'd consider signing him if sterling went to real, but by the same token I'd also consider giving Diaz the spot so he signs a new deal.