Mate can search through the threads an peoples views on McCarthy or transfer targets in general and every one of those points has been raised on a few times
My opinion on why McCarthy is good then, at 22 years of age he has a lot of prem experience under his belt, he apparently has a great work ethic and desire to self improve from all accounts which is often missing from younger players who break into the first team early, technically he's already very very good, has good control and first touch and play at a faster tempo than our current lot have got used to atm, hes also from a defensive standpoint very good at getting in position and intercepting (bit like gibbo in that way) hes got decent pace and looks to bring others into the game.
Negatives, he isnt the most consitant which at that age is to be expected a little, he needs to work on the incisive ball a lot more, and he needs to get a bit more bite or arrogance /aggression about his game to become a truly top midfielder