(updated) Horrible service, use at your own risk.
After I published the bad review finally the customer support was able to provide assistance, it took some effort but the problem is solved. In the end I believe they are are trying to do serious business but their customer supporrt is not the best. My recommendation would be: be cautious, use paypal, and expect that if there are problems it might not be straightforward to get them resolved (also don't count too much on the warranty/returns). Weight the pros and cons for yourself (it will be similar with other Chinese online retailers), but the prices is usually pretty good. I have used them again and all went OK. original review: Got delivered a defective product:. A pre-assemble 3d printer which was not possible to assemble because of a 2mm screw hole mismatch. I requested a replacement or a return. Was asked to provide a video of the problem (which I provided) and was told a solution would be provided in 48 hours. After more than a week and two contact attempts from my side,still no response. Will give them a couple of more days and will then request my money back via paypal.