Hi
No experience with the CZ-550, but the family owns a CZ-452 Merican, hump back stock (European), and a 455 Hump back. Beat a 10/22 twelve ways from Sunday. The 452 Merican was accurate out of the box, less than a half inch group at 50 yards. Two of the three have a 6x Weaver classic, while the daughter's hump back stock has a Tek sight peep setup.
Later