Nothing wrong with the Chinese drums, I got Romanian made ones.
Advantage of these drums is that you can have them fully loaded with the spring not wound up and then when you need 'em all of the sudden you can wind up the key and even shoot them when the drum is not fully wound. Other drums have to be wound up before rounds are loaded in. Check first before buying.
A bit off topic here, but I find it interesting that many in the US seem to consider the Norinco AKs to be some how superior to the other AKs. In Finland the Norinco AKs are considered to be the worst on the market and usually people avoid them and get Saigas and Arsenals(the Bulgarian ones) instead.