I have only dealt with one Chinese dealer, so can only give opinion for him. Taney (Quick CNC) has been great to deal. My router is very well built and I have no complaints with it. The DSP is a very simple control system, but works well.
Keep this in mind. If you don't have a good working knowledge of CNC systems, China may not be your best route for purchasing. Documentation is sketchy, at best, and you will need to install machine yourself. Also, pressing the wrong keys at the wrong time on the DSP can change settings that will cause the machine to malfunction. If you are prepared to handle these types of situations, without a service man showing up, then Chinese machine maybe for you.