I've used this ballast for several years now and have been very pleased. They start RIGHT up and never fail. I also enjoy being able to move the bulbs around within my hood.
My only complaint with the ballast is that one time when I tried to remove a NEW bulb from the socket, the bulb separated from its plugs, leaving the plugs in the socket! Not sure if its the Coralife bulb or the Coralife ballast's fault, but seems like the fit is just a little too tight.