Which model are you looking at? CZ 455's come in different models -- the CZ 455 American with no sights and a sporter barrel, the CZ 455 Varmint with no sights and a bull barrel, the CZ 455 Lux with sights and hogback style stock (suited for open sight shooting) and sporter barrel, the CZ 455 Ultra Lux, which is similar to the Lux but with a 28"ish barrel. These have walnut stocks. All can change barrels between them and between calibers.
The thing to keep in mind about .22 WMR, of course, is ammo is less available than .22LR, it's more expensive, and it is not made in match quality.