Most 7.69X39 imported ammo just isn't pinpoint accurate due to components and Q/C. The round itself can be as good as any others as far as accuracy.
Yes, the recoil is low. I think the bullets are 123 grains in mass and there ain't a lot of powder to be burned. Something like 30 grains, or so? I have only fired one or two rounds of 7.62 x 39 in a Ruger Mini-30. That was over 25 years ago. I never had any interest in owning a 7.62 x 39 rifle until about April 2007. I bought a milled-receiver Arsenal Arms SAS M-7 under-folder (Bulgarian origination), but it just sets in the closet. I've fired it forty times in seven-plus years. It's still in mint condition, not a scratch on it. I don't care for the overly-curved magazine nor for how cumbersome it is (for me, at least) in getting the empty magazine out and putting in a fresh one. So it just sets in its case, never to have the light of day descend upon it.... . . a real shooter with low recoil...
1) Depends on where the AKs and SKSs come from. There is a difference in the way they're madeI don't believe that any round is inherently more or less accurate than any other. If I were going to hunt anything with the 7.62x39mm I would have to use a bolt action or single shot since I live in Pennsylvania. I do have an SKS and I've tried some ammo, notably S&B and Lapua, that can shoot decent groups. Most steel-cased ammo however is 4 - 5 inch on a good day, and the American made ammo uses bullets that are a bit too small.
I don't see any reason why good quality ammo with the correct bullets wouldn't shoot well from a well made rifle. For the record my SKS is of Chinese manufacture. From what I've heard they tend to be hit or miss (pun intended) in the accuracy department. Mine shoots well enough that it would do what it was built to do.