Not configurable Rated 1 out of 5 stars

The sortcuts should be customizable.

This review is for a previous version of the add-on (2.2). 

Customize every shortcut with keyconfig

You can customize every shortcut in Firefox using the keyconfig extension from http://forums.mozillazine.org/viewtopic.php?t=72994. Just install and start it from the Tools menu and change the values for cot2_CloseOtherTabs, cot2_CloseTabsAtLeft and cot2_CloseTabsAtRight as you like.