Good add-on. I used speed dail before but switched because of the firefox-update. This is a good alternative.
Missing is a feature to auto-update the thumbnails but the developer promised to implement this.

For the last few days this add-on got slower and slower. Pressing the home-button leads to 3-4 sec. of unresponsiveness of firefox and black thumbnails. After this time the thumbnails show up one by one so i need ~10 sec. before i can use my dails-page (im not using cloud-dail). Im not really sure what changed. Before this groupspeeddail showed very quick responses.

Edit: The problem was Ghostery. Without Ghostery everything is fine. So back to 5 stars. A compability-fix would be nice tho.