So, to get things out of the way first: http://us.battle.net/wow/en/character/korgath/Grenadier/advanced and http://www.worldoflogs.com/reports/5a62wpc7hdfljzes/sum/healingDone/ (last log I healed most of the fights)
I run 10m normals atm, (supposed to be heroic but yay people leaving!) and my current set up works fine with our heal comp. My only issue with it, is 1) regen on spread out fights and 2) HPS on spread out fights. I have yet to actually OOM myself before the end of a fight like I used to in ToT, but there's been some fights where I ended with ~10% and if it'd gone a little long