I'm pretty sure the double bright would only be good for FW or FO. Aquatic critter has some on their FW tanks and they don't really look all that bright....to me. Aquatraders has what appears to be knock offs of the Marineland Reef Capable Led fixtures. I think they are less than half the cost. I was thinkin' about gambling on the 24" fixture for my 20 gal. just to see how the mushrooms and gsp's would do.
They also have the single bright knock offs and for the 24", I think they are around $40 or so.
It depends, awhile back people complained of fires. I think this was only with the Halide lights and it seems since they switched ballasts, not a issue now?
I started out with a PC fixture years ago and it was fine. I'm actually fixin' to order one of the $70 48" led lights for my FW tank to see how it does. The thing with the cheap lights, most will put them down but probably 90 percent of the people who do put them down, never even owned one.