It's scarily cheap.
The problem with Chinese stuff is that you have absolutely no way of telling the good from the bad.
Not all Chinese stuff is bad. In fact the brand name cool stuff you get is also made in China, and you can get the same quality for a fraction of the price if you know where to look.
I knew a guy who made a living of importing pro photo gear from China, custom branded. From the very factories that make the Manfrotto and similar brand named gear. I got a tripod from him that cost about as much as the cheaper ones you can get at Media Markt, and in construction quality and materials it's up on par with the mid-to-high level Manfrottos. It's a beast, and absolutely beautiful.
However, if you don't... (which is usually the case if you're on eBay...) I definitely wouldn't buy Chinese technology off eBay.