This is my recent experience with a purchase through Cheaper Than Dirt.
I ordered a Century International Arms Chinese Type 53, described as "graded in good condition by Century Arms".
When my FFL opened the box in front of me, we found the rifle with the stock broken in half at the grip. It was packaged in a box approximately 8 inches longer than the rifle, with no additional packaging to hold it from sliding back and forth. The box itself was in good condition (not damaged).
I called Cheaper Than Dirt to notify them. They told me I had to work with Century. I called Century, who notified me they would replace it, and they sent me a prepaid UPS shipping label.
As to the condition of the rest of the rifle: The stock, other than being broken, was acceptable. The breech had some areas of rust. The bolt handle was rusty, the top of the barrel near the receiver had an area of rust about the size of a nickel, the bayonet had rust on about half of it, and the rest of the gun had small amounts of rust. The bore appeared to have good rifling. The gun did not appear to have been treated with cosmoline before storage. It looked like it had been wiped down with oil, but that had pretty much evaporated, hence the rust. The stock was covered with a thin layer of oily dirt.
I've shipped the rifle back to Century and will update this post as events unfold.