The first thing you need to know about DHGate it's like a Chinese eBay with only Buy it now sales. They don't sell anything themselves, instead they broker sales between the seller and you.
The process is actually a smart one. You find what you want, order it, DHGate holds your payment, the seller sends it out, then DHGate releases the payment to the seller once you confirm receiving it.
I've placed 5 orders on DHGate (all at the same time), I received one! I opened disputes for three and received full refunds. The fifth and final order is still in limbo that I suspect they (the seller) is going to try and stall all the way through Chinese new year.
It seems to be a matter of pride for the sellers on DHGate to see how much they can get away with. I've had to deal with everything from fake tracking numbers, substituting for cheaper/slower shipping methods, sellers using multiple accounts, to lying about stock and availability.
In the end It's sadly not worth dealing with the 10 crappy sellers to find the one good one.