Very easy to clean, even if you're shooting corrosive surplus.
It's said that you can take them apart and put them together without tools, and you certainly can for some if not most, but I cannot for the life of me get my trigger assembly back into the rifle without a rubber mallet and a punch. That said, with those tools, it takes me about 10 seconds to do. The lever to remove my gas tube is also extremely stiff, but I can do it with my hands if I wear gloves. Remember, this is my particular rifle (Chinese Military Surplus) and not at all indicative of all SKS rifles. I've had no stoppages/failures of any kind, and it's always a blast to shoot.
Seriously, get one! (or ten) They're easy to clean, extremely reliable and cheap as dirt.