You replied to Fellaini's post by saying that its difficult to judge Carvalho since he is not EPL proven. I only highlighted that since the gap between the EPL big clubs (ex Man United) and smaller ones (ex Everton) is enormous, then using the EPL proven thing as a way of judging a player is wrong.
In my opinion Fellaini and Carvalho are at the same level in terms of whether they can succeed at OT or not. Fellaini has the advantage of being older, he's got more experience at national level and had been in England for enough time to say that he can settle in Manchester . Carvalho seem more technically gifted and hes a Lisbon talent ie he's used to pass to feet football which makes him more suitable at United as opposed to Fellaini whose used to the Moyesy 'Everton way'. However if you ask me whom I prefer at OT Id say the latter.