IMHO: The postal systems in China and Hong Kong are terrible.
If you're in the USA - add on the cost of DHL shipping and you're even with buying from the USA suppliers and you'll get your delivery in less than half the time from a US supplier. Use regular shipping with China and it takes weeks to get things.
Sorry to be negative, but this issue with Hong Kong now x-raying every package soured me on buying from China and Hong Kong.
I've got an order for a charger from Fasttech that's been sitting in Hong Kong since August 30th with no movement.
No batteries and no juice, just a charger. My advice is to look into more US suppliers that keep their mark up low.
For example check out
DesertVapes Electronic Cigarettes and Supply
Not to be confused with High Desert Vapes - Desert Vapes has fantastic pricing and super fast delivery.
There's a bunch of other US suppliers out there that price fair and save you a lot of aggravation over the china sites.