I have one of these and it has been doing well for almost 2 yrs. Green star polyps, green striped mushrooms, Kenya tree, small hammer, Candy Cane, Finger Leather and Xenia are all doing well. Zoas seem to want more light than the 24w so I will move them to another tank. Be sure to change out that bulb about every 10 months, you will see a big difference in coral health when you do this. Things will slowly dim and soft corals go dull brown when the light is at the end of its days.
With such a small space you have to watch your spacing to be sure sweepers are not reaching out and damaging neighbors. Also be sure to do a 1g water change weekly. It's easy to build up toxins in a small tank like this. Carbon, that too. Enjoy!