Yeah, Maneskin are all the rage in Italy now, they also won our "national" music contest (it's a festival of italian music that takes place in the town of Sanremo, so "Sanremo" itself became a methonym, like "White House"... in Italy you just say "Sanremo" and people recognize the festival which is very famous here) which gave them the chance to take place in Eurovision to begin with.
I didn't bother to listen to them and I only heard their winning song, gut feeling is that it's a band that the kids like (the singer is hot and also has that "damned" look and attitude which helps) and that actual and longtime rock fans won't find much to enjoy in their music, but hey, it's rock n' roll, it's music played with real instruments, if some kid starts to listen to rock because of them and then finds out the "real" rock players, what's wrong with it?
Also, the singer saying on the Eurovision stage "Rock n' roll never dies" is probably the best thing happened in the contest since Lordi's victory in 2006.