Is it a very high quality build, say as good as a Polytech?
yes. the build quality is darn nice. the finish is better than any poly (i still have a poly legend fixed stock). more importantly, orf backs up what they sell in a way the chinese can not.
Also, I know this is a very relative question, but will a good quality AK 74 tend to shoot better groups (say at 100 yrds) than a AK 47?
as a rule, the ak74 outshoots the ak47/akm...individual examples of each not withstanding the norms. my poly legend is the most accurate 7.62 x 39 ak that i own. my sar2 will out shoot it.