I don't have a pond breather, but having used a de-icer over the years I don't recommend it. The problem we have had with ours is it won't sit upright in the pond. It's a design flaw with how it's weighted or where the cord is or something. And unless the bottom of the unit is in contact with the ice it's useless. If you have an iced over pond and set it on the ice, it will melt through. But if you try to be pro-active and put it in the pond before it freezes to keep the pond from icing over, it's like a Weeble - it wobbles. Haha! I don't know the actual brand we have - there's no branding on it, oddly. I've seen others that are more disc shaped that would sit flatter on the pond, so those might do better.
If I were going to replace my de-icer, I would choose a pond breather instead.