The CZ-858's I've seen are junk compared to the Norinco M-14s models I've seen... is the Norc M14s a well-finished rifle? Not really, in terms of the "little stuff" like seeing machining marks everywhere... but mine shoots just fine, and it feeds dependably with all kinds of 308/7.62x51 ammunition. Obviously something USGI through-and-through is going to be better, even on a Norc receiver... and an LRB or SA package is sort of the 'holy grail' of M1A-style rifles (for good reason). For its price, you have to admit the M14s gives pretty good value though.
The stock furniture on the 858's is disgusting to look at, IMO - and the rifle's not made much better. That said, if you know how to clear malfunctions now and again, it's not THAT shabby. The only plus point for the 858 (in my opinion) is how amazingly inexpensive the ammunition is. This is a major plus, mind you, so I'd probably own one somewhere down the line. Nothing like being able to stockpile 10k rounds in the basement, in sealed tins, for $2k or less.
For my money, I'd buy 10 Russian or Chicom SKS rifles before 1 858 though. Same cheap ammo, FAR better construction. The 858 is a fun range novelty, but to "reach out and touch something" my M14s is the only semi-auto I like as much as my AR15.
The thing is, however, that we're comparing apples to oranges - the 858 is NOT a main battle rifle, as mentioned. I've shot them, and they're sort of fun... but I wouldn't spend money on an 858 that I could spend on an SKS or M14s.
-M