I am not sure that they are "better" than MH
beats a T5 in intensity hands down I would think. They are cheaper for sure. Although the T5 bulbs last longer, you have more to replace. Someone with alot of time on their hands can do the math. MH
bulbs last a year. T-5 HO
non actinic bulbs last 2 years while the actinics last 18 months is what Foster & Smith says on their website.
General Rule of Thumb is 4 wpg
for most corals is a good average. SPS
corals and anemone, higher lighting.
You have a pretty small tank, so I would think you would do fine with T5..all the previous is just trivia.