I realize you are asking about a JW-103 in 7.62x39. I have a JW-105, .223. 22" barrel. It shoots just fine. I took it out to my friend's place and we sighted it in with Chinese ammo, either no name or Norinco. He is a real fussy shooter, has high end rifles, and even he was impressed. It isn't much to look at, but is a nice little rifle to shoot.
I would have tried a 103 as well, but when the urge struck, none were readily available so I bought a Zastava instead.
Now that I've said that, I shall have to dig it out of the pile and give it a run.