I have been very fortunate with HK, yet I limit my purchase to a dollar value that I am willing to risk burning. The term roulette wheel comes to mind when dealing with HK. There is horror story after horror story and the examples do mean something. Granted there are complainers that no matter what you do you would never satisfy, yet many folks that have gotten shafted by HK are on the legit. Since they have the US locations things have improved significantly.
HK does sell a lot of items cheap and also a lot of items
are cheap in quality. I think the best bang for the buck with them is batteries. In a lot of cases you can buy three (or at least two) batteries from HK for what you would pay for one battery from other suppliers. This is a substantial savings and some of the guys I know have compared their batteries side-by-side others and they are as good as any out there that are comparable.
At any rate, use caution and also spend some dollars with our US suppliers too. Life is good!