just picked a cz 858 non restricted on cgn, great price, uses the corrosive ammo, but as said ammo is cheap enough to go plinking, and the caliber is consistent with the model of gun.
if going with 223, i would personally go with an ar 15, and many great examples on the cgn exchange.
as for corrosive ammo, if you google about its negatives, it all goes to stripping and flushing with hot water, before application of solvent and gun oil, for some with blackpowder experience from the old days, even before pyrodex, the extra step of running it by showering the parts in the bathtub is not troublesome or time consuming. i shoot blackpowder.
either choice as to the mini is quite fine, but imho, go with the 30 and pick up a crate of ammo at the next gun show in your locale. regards.