only the yugo 59/66 has the grenade launcher, grenade sites, radium flip up sites, and gas switch. the yugo 59 looks like most other sks rifles.
pretty much if you get a 59/66 and the gas switch is easy enough to move without tools, you shouldnt have a problem. firing 3 rounds through one would render the most pitted barrels shiny as new again.
I should know, i have cleaned/repaired over 100 of them for a dealer. i found them clogged with cosmoline. the cosmoline even kept some of the grass green that we found wedged into some of them. its almost like someone practiced with the rifle in the morning and in the afternoon dunked it into cosmoline. i found them with art on the stocks, intricate serbian crests carved into them, names, stickers like superman and my little pony stuck to the stocks.
I have the yugo 59/66, the yugo 59, the chinese M21 (no chinese character variant), a romanian, a russian from Izhevsk (lots more rare than the tula "star" version) and the albanian sks.
Looking for a russian stamped receiver sks, an east german, north vietnamese, and north korean variant, but they are very rare.
maybe its just the purist in me, but the plastic stocks, extended mags, bipods, scopes, etc, all just look silly to me on these guns. Its kinda like comparing a factory honda civic to a riced out one.
RIP Mark 1977-2005 I miss the hell outta you bro.
Happiness is a warm AK
If guns cause crime, all of mine are defective."