is the best I cant argue that but there is other Lights that are almost as good without heat problems
T5 give off alot of light and give off little heat, There was a guy on reefcentral that had his tank out of t5 it was gorgeous.
will heat up your water in your tank they get very hot. SPF corals you can go with t5.
theres a good forum of this on reefcentral.com that may ask your questions. They have alot of lighting experts and can show you what t5 can do.
Or if you have a LFS
that has different lighting in there tanks take a look at them and decide. Everyone has there own opinion on lighting. I use PC
right now but going t5 very shortly.