I am running 2 of them on my main display along with a ice cap for de center bulb. they are all 3 250w and they seem to work fine, but i like the icecap far better. The coral vue can be picky with higher k bulbs and older bulbs it seems, sometimes they do not fire and then the icecap fires quickly. but for half the price of my icecap im happy with the two. if you can find a decent priced icecap i would do it or if you get the coralvue cheaply like i did you will be happy.
I started out with 2 Coralvue ballasts and then switched to icecaps. They worked fine but had a interference issue(noise) with the orig RKI controller.
They were a good deal for the money and would use them again if I needed too.
I have 4 Coralvue ballasts, 2x250w MH ballasts on the tank, a VHO ballast on the tank and a 250w MH ballast as a spare whcih I have loaned out since I have never needed it yet. Customer service is great and they seem to work as well as or better than the magnetic ballasts and Sunseeker they replaced.