I have a CZ 457 in 22 Mag. I put a Lilja barrel on it, and it shoots very well.
I also have a CZ 457 varmint in 17 HMR and a Ruger American in 17 HMR. The CZ is a much better rifle all the way around.
My personal choice would be the 457. I like wood and steel. Either one would be good for killing a tennis ball at 100 yards.
Nothing wrong with the Ruger if it tickles your fancy !!!!