I wouldn't go with one. Coralvue has had some pretty tough luck with a hurricane wiping out their office. I think they are back on track now though, however I know a guy who went through 4-5 of their 175w eballasts. Wasn't too encouraging. I strongly recommend looking at EVC's electronic ballasts, everyone who uses one likes them. (myself included) Vince is topnotch when it comes to customer service as well.
www.oceanencounter.com