Due to the lack of setting the GPS to MPH and inability to download videos with speed/location I will be returning the 70mai pro and gps that I received today. I've investigated the 70mai a800 and determined it lacks these same two features.
Not sure why anyone in the US would want GPS that could only report KPH.
There's another thread with guidance how to extract the speed/location from the video when playing it on Windows. As for KPH/MPH, it could be implemented as a small change in that tool, but I guess that's no longer relevant since you're returning yours.