Post-Fergie: Which players have come here and performed equal to or better than at the club they were purchased from?

Bruno had a good 18 months which is quite long for a United player and other good spells more than others possibly.

Romero.

Cavani and Zlatan did what I expected, short lived quality. Top stop gaps for a season.

Varane has done well.
 
Easy. None.
I think the shouts for Blind (totally forgot about him) are really good and after that, it's a sliding scale of sorts with someone like Bruno being top end as he has been the player I think it was Sporting SP profiled pretty accurately.

But overall, it's just an astounding failure rate over such a long period of time that it boggles the mind.

So many players came here as our new dawn and got Space Jam'd to our bar rather than elevate it or themselves. I don't know who we'd be par with for failure rate on transfers in the PL these past 10yrs.