garmin extrex vista cx does not work with parallels actually, that understates it... i have not been able to upload maps to the device - it gets almost to the end then blue-screens and reboots the windows VM. I thought updating the firmware from 2.6 to 2.7 would help...bad idea. Crashed and rendered my CX completely useless and had to ship it back to Garmin. I then successfully updated a second CX using the mac updater but still can't upload maps to it. I am on build 4128, the latest, of parallels. Extremely frustrating to have spend $600 or so on GPS and I can't use it.