[Feature request] wipe device before restoring backup

Thanks for pyTomTom, it removed the last show stopper in having my Dad migrated from Windows to Linux.
Main use with PyTomTom is to switch between two maps (no room for both of them in the device).
Basically installed map1 to device with TomtomHome on windows. Then used pyTomTom to take a backup.
Then removed map1 and installed map2 with TomTomHome on windows. Then used pyTomTom to take a backup.
Now it's possible to switch between maps by restoring desired backup.
Minor annoyance and the source of the feature request is that when restoring backup, I will run out of disk space in the device and restore fails.
Feature request: when selecting restore backup, ask user if he wants all files on device removed before restoring the backup.
If yes -> rm -rf /path/to/device
then restore the backup.