The Sisters is waaaay evil! And, I tend to say the Loxodon is pretty frakking uselss (yay, a Battlestar reference, what a true GEEK!). Sure, regen is nice, but this is garbage compared to a lot of the other avatars out there. I guess with the GW token armies you'll have lots of stuff to sack. Then again, with a GW token guild deck, you'll likely use some other creature-centric avatar.
I wish I could win a Sisters. I just might try out an event, unless the price on those sisters is low enough to just trade for.