Someone described him as a big cat prowling around the penalty box. I like that description.
I only have two concerns:
1. Keepers live and die on confidence. As we know all too painfully. Does anyone know how he reacts when the inevitable happens and one of his drag backs or cute footwork gets charged down successfully by a striker?
2. He does seem to parry the ball back into dangerous positions. I think part of that can be mitigated by the fact that a lot of those parries are very saves that most keepers wouldn't have made in the first place. Also by way of mitigation, his reactions are very good, so it's not as if the loose ball is a guaranteed goal for a striker following up. But can anyone else offer any comfort in that point?
But make no mistake, I am happy. I would have had Karius back as first choice... I like him, and I'm not going to write him off on the basis of one game (putting the concussion to one side completely). But, that said, even ignoring the CL final, the goalkeeping position is one which could be improved and we've now bought the best, available, player in the world. So fair play to those who made it happen.
One other thought... I don't agree with the argument of "a keeper should never cost 60m" etc. Same goes for fullbacks too. Its supply and demand. How many truly great goalkeepers are there in the world at the moment? Not many, therefore they're at a premium. Also, you only have 11 players on the pitch, so why ignore one of those positions? I'd rather have a top class keeper or fullback on the pitch than a top class striker on the bench.