The electronic ballast "should" produce less heat (both at the bulbs and ballast), use less electricity, and the bulbs should last longer (because of heat and the flicker of magnetic ballast) As far as how much heat, electricity, and bulb life I have no idea, I'm sure it depends on each unit, not just each brand. I have no experience with Icecap ballast but any brand electronic ballast should give you the better results than a magnetic ballast. I'm not saying you have to use electronic ballast, and is some cases the magnetic will perform almost as well.
By the way everything posted above is from my knowledge as an Electrical engineer, I've never tested them side by side.