FYI – I think I found the answer to my question elsewhere – posting here in case anyone is interested.
Looks like I found a solution. I posted to the forums on VideoHelp.com and someone suggested VoltaicHD and it seems to work perfectly. It was specifically designed to convert from .mts (AVCHD) to formats that people can easily edit on the Mac or PC.
https://www.videohelp.com/tools/VoltaicHD#features
https://www.shedworx.com/node/250
Arturo