I have a 4 bulb Catalina on my 75g. I'm now going to replace them with a similar model to Burr740. The reason being is that the spread is terrible. All 4 bulbs are pretty much side by side. Maybe a half inch to an inch apart. Granted each bulb is separated by a reflector, but the fixture is only maybe 1/3 of the width of my tank. This all adds up to a lot of light being forced into the center. The fixture does light up the whole tank, but its definitely less in the front and back than it should be, and accounts for the fixture getting hotter than it should. With out forking over $400 plus dollars on an ATI unit, I think the best replication of these lights are hydroponic T5HO fixtures.
Catalilna had great customer service, and the light was nice, and for a $130 with bulbs you cant go wrong. At least I thought until I seen some of the hydro setups for around the same price.
IMHO if your going to go T5HO stay away from lights designed for aquariums. They're going to charge you more for less. All of the brands like Aquatic Life, Coralife, etc etc are overpriced, and they are not as good. Some are pretty much junk IMHO. Minus Aquatic Life of course, but when you consider the price difference to a Hydro unit they don't even compare.
There are a few concerns for me in regards to going with a Hydroponic T5HO light though. For starters there seems to be a lot of generic brands, and its hard to tell which ones are tried and true, and last but not least most of them are built to grow terrestrial plants in a commercial environment so they are not very aesthetically pleasing. It can be hard to find a fixture that looks good or doesn't look like it belongs in a shop.
Here are a few I'm thinking of going with:
Amazon.com : Quantum BadBoy T-5 4 ft - 4 Lamp Fixture 216 W : Patio, Lawn & Garden
Amazon.com : Hydrofarm FLP44 T5 Designer 4ft 4-Tube System w/bulbs : Plant Growing Light Fixtures : Patio, Lawn & Garden
If anyone has any experience with either of these lights plz let me know.