I am quite pleased with the Dark/Dark tanker, a new possibility in this release. The set drinks endurance like nothing else I can remember, though. Even with endurance reduction in all toggles, I spent most of the Frostfire mission with all toggles off to save energy. I have now upped to two endurance reduction slots in each toggle. The powersets are great for soloing though, and would especially shine if you team with a kinetic. The attacks are a bit slow but do a good deal of negative energy damage, which is poorly resisted except by supernatural beings. And the defense gives superior damage against them. So in either case, you don't really have the weak spots most tankers have. Your weak spot is the enormous endurance drain, which forces you to pick what toggles and attacks to use.