User blog comment:Ancientaura/DLC questions.../@comment-1808057-20100312202501

Yep. Knoxx is the best one so far, and it's really the only way to make it to 61. Zombie Island is good as well, but Knoxx is the best in my opinion. The Underdome is really only worth it for the bank, two skill points, and a bit of an extra challenge.