Not sure what deals, if any, 3DR has with the Chinese wholesale market, but it is interesting that one wholesaler has a "genuine" 3DR APM V2.5.2 board with a jumper pad to enable / disable the on-board mag chip to allow for an external I2C mag/GPS board -
Scroll down and look at the back side image.
Chris A., is there any way you can stop the Chinese from doing this if it is an unofficial copy with your branding printed all over it? I guess it is the branding that becomes the issue and not so much the hardware which is open source?
Was considering my options for my new online store to make APM's available, but certainly not dodgy copies from China.