Ouch, I just looked at the price sheet and adding a couple of the medium sized units will cost more than retail on a dual MH ballast bulb setup, esp if you need a lot of pipe to span roof to ceiling.
On the other hand, over the long haul, the natural light added should benefit a reef and maybe allow one to use smaller lights, say 250 watts rather than 400, esp if you have a fish room thats a fairly low ceiling and don't need $100 worth of extension pipe to get light to the tank. OVer the long run it could pay off, but in the mean time reducxed electrical consumption is always a good thing
