Based on a small sampling, I disagree about fit and finish. Yugos are carbon copies of the original Russians, and solid as a rock. The Norinco my friend replaced his Yugo with was NOT as solid, and the ones I've seen/handled at gun shows were the same. Not poor, but not superior either.
I think the lightened weight and chrome lined bore are the two big selling points for the Norinco. Plus they aren't sending any more over here.
Gas valve issues occur only with used/issued Yugos that shot corrosive ammo and weren't cleaned well afterward. Most Yugos I've been seeing have been unissued/excellent, so that's less of an issue these days.
The heavier weight of the Yugo, plus the added muzzle heaviness CAN be a plus...depending on what you're looking for. They both reduce recoil noticeably, and some people like the balance a bit better. But they do also add noticeable weight and decrease pointability. Plus there is always that cool golf ball launcher attachment for the 22mm NATO grenade launcher on the Yugo. I've ordered one, but it hasn't arrived yet, so I can't report.
However, the lack of a chromed bore means the Yugo is more susceptible to heat, and a bit more of a chore to clean.
I agree with those who would get both, though.
