You might as well get a CZ in .458 Lott. The extra long magazine doesn't do very well with .458 Win Mags and they will shift position under recoil. That long magazine is used for both the Lott and Win Mag rounds in the 550. A Win Mag length cartridge can be fired in the Lott for practice and in an emergency. But if I was using a CZ 550 for a dangerous hunt, I'd want the Lott to add a little more insurance that the rifle will function to its top potential using a cartridge that best matchs the magazine length.