This is the setup our 10 man alt raid used. We progressed from 0 heroics to 14/14 hc without outside interference (25 man boosting).
Something you don't expect is that on some fights, you really notice the lack of healing throughput - we were lucky enough to also have an enh shaman for AG etc (who went resto for 3 healer fights, so we actually had all the healing cds needed). But on a fight like Paragons, you notice the lack of raw throughput during parasites etc really badly. Or Garrosh intermissions.