I caught a couple of their games last season, I'm not going to claim I paid loads of attention to them or the way they played, but the games I did see, I actually thought he had Napoli playing OK, gave both Inter (1-1) and Juve (lost 2-1) decent games, beat Milan 1-0 away (though that was more of a grinder) beat Fonseca's Roma away 2-0.
I think I may be alone on here in saying I'd probably prefer Gattuso to Fonseca, but I also think there are more interesting coaches in Italy, like Roberto De Zerbi (Sassuolo).