I actually think that I'm going to OS gloves on the T13, if I recall from my gear list.
Right now, I'm trying to pick up 2 T13 to run 2 13/ 2 12 for the extra mana while we push through the early hard modes. As far as picking up the four piece, I think it's really going to depend. A lot of rejuv is overheal, even in heroic. I think the only way to know if its got value or not will be to test it out and see if our rejuv overheal stays static or inflates as a result.