The AT-AT is by far the best out of the three. Imperial design translated perfectly into a powerful speaker design. And the artistic license with the colors pays off.
R2D2 is also in top form in this speaker system. Unlike the AT-AT, color is what brings that unforgettable personality to this sound system.
The golden AT-AT just doesn’t compare to the other two (the gilded look doesn’t match the powerful image of the walker), but I did link to it through the icon at the top of this article.