Dont base your opinion of a VZ58 on an SKS. There is no comparison. After buying a VZ58S, I sold my SKS-D. The SKS-D was a good, reliable,cheap to feed gun, but the VZ is way more accurate. I have a cheapo red-dot on mine right now,and it is very accurate. I like my VZ so much, in fact,that I sold my Armalite M4 because The VZ is so much cheaper to feed, and reasonably accurate.
That said, I was playing with a Norinco M4 the other day, it felt like a pretty nice gun for 900 dollars. Both guns have a really good piss off a lieberal factor, so you cant go wrong either way.
I would go with the VZ/CZ858 just for the cost of ammo.