The skS [semi-avtomat Shpaginova iirc] is a dandy little carbine. Fires the .30 cal Soviet short which is about the cheapest centerfire round out there & about the equivalent of a 30-30, so don't let anyone's complaints about how underpowered it is get to you.
Soviet infantry doctrine of the time figured heavily upon human wave assaults so the sights weren't expected to be accurate, just "close enough." Most aftermarket sights use the action cover retaining pin as an anchor, and therefore have non-repeatable zeros: you've got to sight in again after every cleaning. Replace the issue peep with a Mojo and get the front sight adjusting tool [works on AKs as well] and don't look back.
The standard wood stocks are normally poorly inlet and composed of random species of firewood: unfortunately, due to insanely unconstitutional federal meddling, you have to change out way more parts to US made components if you change out just one (the stock), as doing so takes the rifle off C&R status. Go figure. Unfortunately #2, the issue stocks are almost of too short a pull for normal-sized 'murricans. If you go down this route, do not waste time with anything other than the Dragunov style stock: it is a massive improvement on the skS ergonomics & handling. Downside there is that the manf. cheaped out on the mold design, & you have to go in & modify the stock by cutting a notch in it before putting the gun in so that you'll be able to remove the action cover for cleaning. Otherwise, you'll be stuck having to remove the receiver from the stock every time you want to clean the gun [which is a pain since it latches in nice & tight.]
The trigger is not as atrocious as living w/ a Glock, altho' it's gritty and there's tons of trigger slap. No, I mean more than that: your finger will be pretty dang sore by the end of the day if you shoot a couple of hundred rounds thru it. Is it worth spending the money on a trigger job? Depends on how much you us the rifle: if it's truly a truck gun & the most you fire off in any one day is a few rounds at coyotes or something, then probably not.
It's a good, rugged little unit, and when they were readily available for <$150 back in the '90s [which is what, equivalent to $300 today, what with inflation from Clinton, Bush II & massive inflation from the Obamanation regime] they were a smokin' deal. Yes, the stripper clip loading of the fixed magazine is less than ideal, but if you live in free america you may be able to get the "paratrooper" model that takes swappable mags. Not here in the PRK, they're on the banned list.
As for which are better, the Russian, Albanian & Yugoslavian models w/ screwed in receivers generally are considered superior to the Chinese models w/ pinned on barrels, altho' I've no complaints about my Chin Alpha branded cheapy. Obviously, the ones with more machining involved in their manufacture like I just mentioned cost more. (Go figure.)
The Yugoslavs don't have chromed barrels, so are more maintenance intensive when used with corrosively-primed surplus ammo. Again, no problem for me since the PRK bans them anyway because of their grenade-launcher muzzle weight. No chrome lining means the Yugoslavs are potentially more accurate, so if you're loading your own w/ non-corrosive primers then peachy, but every skS I've seen beats the heck out of steel cases, so I'd hate to see what one does to actual brass ones.
There, that's the 5 minute run down on pretty much everything I've learned about the skS in the last 15 years. Good luck!