I remember ALOT of supporters criticising Ramsey in his early days at Arsenal but credit to the player, he put in extra time in the training ground, worked with former class midfielders and turned himself into a top-class CM. If Oscar can add to his game and become even 70% as influential as Ramsey, every Chelsea supporter would be delighted and we would be much better off as a team. As for United, out of the list you provided, I'd take Welbeck because he's homegrown and he would probably be useful as a striker/winger off the bench..