Would you just stack resi or go for a mix of resi/stam (till X k hp)?
I'm more looking into a class with a tanking spec. I have a resto druid myself and yes they are quite good FCers.
It just seems so difficult to choose. All 3 have a silence, warr has 2 charges to get out of trouble and some nice CDs, but no heals. Pala and dk have heals and also some nice "oh shit" buttons.
Demo lock with a pocket healer is pretty sweet. Up to 30% extra healing and glyphed soul link gives 25% damage reduction. Also, in demon form, you have like 20k armor.