I've owned an unissued Yugoslavian 59/66 model for about one year. It is a sweet shooter and has never malfunctioned. My son has a Norinco Chinese SKS with the folding stock and it has also never malfunctioned.
The SKS has to be one of the world's most versatile rifles in that it can be used as a hunting rifle, plinker, defense, etc.
Drawbacks? For me, the wooden stock is too short for comfortable shooting so I just bought a used Monte Carlo black fiberform stock for $20 which will do wonders for my accuracy and comfort. Also, a special tool is needed to sight-in the front post for accuracy. Once the SKS gets properly adjusted and sighted in, it can be a deadly accurate field piece.
There are aftermarket products galore for the SKS and the ammo is fairly inexpensive.
Go here for a ton of useful info on the SKS:
http://www.surplusrifle.com/sks/index.asp
Go for it! The SKS is a best bang for the buck.