Anything Chinese is good. Saiga is the real deal, made in Russia and caliber choices include 5.45x39, 223/5.56x45 Nato, 7.62x39 and 308/7.62x51 Nato. Many different opinions out there, might try looking around at
www.akfiles.com or
www.theakforum.net both dedicated AK sites. The ones made by Lancaster have had problems. Century Arms International CAI is making one with 100% USA parts, I saw the NRA TV show did a test on one a while back and they liked it. Or if you like to tinker and build things buy a parts kit and build your own. The two sites listed above have all kinds of info on how to build one from a kit.