When it comes to booze, cheap means fake...... pay normal price for the real one. i tried taobao many times. i would recommend ketel one vodka. price is reasonable and the taste is good.
I am just gonna bump your question, cuz I am curious about it too...
just an advice, you see foreign imported beers in supermarkets, buy a can instead of a bottle, its difficult to fake the beer in tin then in bottle. I tested this theory many times, it didn't taste funny as a usual fake beer does (I've had my share of fake booze here).