There is a stack of them really, but I'll focus on the major ones as they are the ones that cause most problems for people when doing business with Chinese suppliers.
Biggest Pro, well that is essentially the price, so that's an easy one!
Biggest Cons, very first one to watch out for, and the one that gets most people burnt is buying branded goods. No matter what the product, no matter what brand, you are not able to source authentic branded products from Chinese suppliers.
You can source some excellent replicas, designer inspired goods and of course really bad fakes, but always remember that no matter what they tell you, the products are not genuine, and will be illegal to import into most countries if they are branded!
Second biggest con is the con itself. Scammers, they'll take your money right from under your own nose if you don't do the research required to ensure they are a legitimate supplier.
Stick to those main rules when dealing with China, and you'll be off to a pretty good start!