Did you ever decide on a camera?
If you decided on a QHY, I hope your experience is better than mine. I had purchased a 268C, Early Bird Version, and when I got it and connected it all up I had lots of connection issues. When I asked QHY for assistance all I was told that the camera had been tested before shipping and that it was fine (I had bought it directly from QHY). Well, after some time it started working fine and I left it on the scope and didn't touch it. I then decided to set up the camera on a different scope and I again got lots of connection issues. Then I noticed that the USB connector was broken which was probably the problem all along. Anyway, I sent the camera for repair through QHY repair service in the US. The camera was then sent to Hong Kong. After a couple months I sent them an email asking for an update and was told that the camera could not be repaired in Hong Kong and therefore needed to be sent to Beijing. I sent them more emails with no response until after 5 months when I finally heard from QHY and was told that they would replace the camera. I received the camera today, but what I got was a used camera and not even the same model camera. I had sent an Early Bird version and what I received was a Photographic version. From what I remember there was a significant price difference between the two versions. To say that I'm not impressed would be a major understatement.
I hope your luck is better than mine.