I don't know why, I don't really like Redemption. It probably is one of the, if not the most, useful support items for teamfights, but I don't like the small heal, that even if it hits the entire team will be an enormous heal, and the small damage it does to the enemies. It might hit 600 true damage if it hits everyone, and it might heal 1000 health or more if it hits all your team, but that kind of situations are really specific and slightly hard to make happen, as in a teamfight everything happens too fast and people normally don't think a lot.
But, in a game with friends, in which we can organize ourselves, I'd take Redemption.

And yes, I just wrote that for no reason, when I could just have written 'eh, I don't like it'.

Edit or something:
Well, another thing I just thought of. Redemption is kinda like a Bard ult. It requires a great situation to find the perfect moment to use it, and that takes so long to occur, that you just use it in a situation where it could be useful, and don't always get it's full potential.

Double Edit:
And both are a circle.
And I don't like circles.