He's everywhere, has a good touch... really looks to add quite a bit to our midfield. I say go for the 433 with Marchi and this man next to Pirlo. Those 2 will be the engines of the side and can offer plenty going forward if the opponent allows it.
I'm sure Marchi will start next to Pirlo again next week, but I don't think Conte can justify that much longer if Vidal keeps performing. I guess it also depends on how the attackers do.. competition in the squad.