Rated 4 out of 5 stars

Very nice and works well.
But I can't add a gesture for Pin/Unpin tab and go to Tab Group.
I really hope the developer adds the support for those features.

This review is for a previous version of the add-on (1.7.0.1-signed). 

No built-in functions for pin/unpin at the moment but you can use a custom script. See http://forums.mozillazine.org/viewtopic.php?p=14179319#p14179319