Like anything that is mass produced, you are going to get some units that just don't function properly. It sucks, but it's a fact of life. I can understand you're frustrations, but you have to realize too, that you are not the only customer that CZ has to deal with. Frankly, I think them sending you a brand new rifle speaks volumes, albeit taking longer than you would have liked. To be honest, the problems you are having are probably of a minor nature anyways. A round not feeding from tha mag, could be something as simple as a rough feed ramp, a bad mag, a burr some place, etc. In retrospect, the accuracy issues could also be quite minor. Either way, not all gun manufacturer's would offer to send you a new rifle. At least not before they really ran you through the ringer and did everything they possibly could to get you to accept and be happy with the original gun.
"Lemon's" are just a fact of life in today's mass production way of life. I once bought a brand new truck that was a lemon....it happens! You need to go with what the masses have to say about a certain product, and it's current reputation through other's experiences. I was always a stout Remington 700 man. For me, there simply was NO OTHER rifle alternative. Well....sad to say that Remington's rep has gone way down over the last few years. More and more defective, inaccurate units are showing up, according to recent purchaser's. Enlight of reading up and listening to many other peoples' opinions, I opted to buy a CZ 527 Varmint in 204 Ruger. So far, I have mixed opinions on it. The bolt kind of drags a little, and has some side to side play in it, but it feeds pretty decently. The wood was touching the barrel along one side of the stock, but I took it apart and filed it down myself. The fit/finish on the unit is marginal IMO, but I only beat rifles up anyways...so looks aren't that important to me.
All that being said, the gun has a supurb set trigger...the best in the business. It also shoots like a champ so far.
The main thing I dislike about my rifle, is the lack of an aftermarket for parts. Sure would be nice to have some synthetic stock options, after the fact.