The reason why most endgame tanks run high health is because they build for veteran trials where more health is beneficial/needed and they are mostly DKs which scale very nice with high health. For Dungeons 30k+ plus is absolutely enough.
Thanks. Yeah with even a decent healer over a long boss fight I can get punched in the face for a few million and never lose aggro. There are some mechanics that come close to one shotting me if I get rooted, so wasn't sure if I pushed 40k at the cost of stamina if it would be worth it, though I do a lot of solo, and the damage from my solo 2H style comes in handy.