I recently got the badge chest http://thottbot.com/i34921
Gemmed with 9 healing/2mp5. I got the 5 spell crit/2 mp5 gem from H-SL. With full 25 man buffs I'm sitting at 30% holy crit and close to 1800+ healing. I'm not likely to replace that chest piece any time soon, I'm not sure which gem is more beneficial at this point.