Level 37 SCH here:

After leveling an ACN from 1 - 30 I was ecstatic to finally get a healer pet, not only did it alleviate my Physick spam heals but it also provided me with a lot of room to DPS while "healing". While do agree that the pet AI is god awful I still stand by the fact that SCH heals are quite good. Once you get the hang of your pet, as well as when it will throw heals out (when a target has lost 20% of their max hp the fairy will toss a heal to them), SCH healing becomes rather easy. Sometimes if a tank is good/geared enough I won't even have to throw heals out - I'll just use my 3 DoTs and then spread them with Bane.

If I had the choice to pick between a SCH and a WHM I'd choose a SCH anyday. I'm a big fan of the mana returns that SCHs have access to as well as the fairy and the DPS potential that it provides to the user.