I have a CZ-452 Style for better than a year now, that I've tweaked, and it is a Great gun.
It's as accurate as my custom 10/22, except follow-up shots, but I think it's me more than the gun.
The folks at RimfireCentral in the CZ forum
are devout followers and Junkie/Enablers to the Brand.
Those that have the 452 are glad they have them and want more.
There are more than a few that complain of Bugs in the 455 that they bought.
Some have both and like them but praise the 452 as a better gun, that has all of the bugs worked out.
When someone has to send a gun back to the factory they let everybody else know about it.
You should scan some of the threads there and make an informed decision.
I'm very happy with my 452 as a Bolt action but one is enough for me.
I prefer the 10/22 Semi Auto for follow-up shots, as I don't break my cheek weld.
As said, there a few 452s still out there but the choices are Very limited and that is what I would recommend.
Whittaker, in KY
has a CZ 452 American .22cal / .17HM2 combo for $369 while they last.
That's $40 less than I paid for my Style.