Wonderful...but the keyboard shortcut. Rated 5 out of 5 stars

The addon is perfect but I love using keyboard shortcuts, I think you should be able to change the default one to one that you want.

This review is for a previous version of the add-on (0.1.6.1-signed). 

You can change keyboard shortcuts from about:config page, see notes for extensions.privateTab.key.* preferences:
https://github.com/Infocatcher/Private_Tab/blob/0.1.6/defaults/preferences/prefs.js#L9