I've bought many times from dx.com - starting more than 3 years ago, when it was dealextreme.com - and everything has been to my liking.
On 2 occations I have had to contact DX with a failed item, and both were handles swift and very well!
Alså their online chat function works very well.
Delivery from China tends to take between 2-3 weeks, until it gets here (Denmark), but feedback from DX makes it easy to do track-and-trace on your delivery.