Yes I am growing clams and SPS corals with no problem in the sandbed which is 24" away from the lights. I have lots of
growth and no problem with coloration. There are lots of threads on RC that talk about T5 lighting if you would like to learn more check out the
lighting and filtration section.
The one that shows PAR values for different T5 bulbs is started by a guy named Grimreefer. There are still many people that will tell you that you need MH to grow SPS or to have the "glimmer lines". I can live without the lines to save as much in electricity and heat as I do by avoiding MH lighting.
I bought the reflectors at Salty Critter which is a local store for me. they are available at marine depot for $33 each. reefcentral does not allow linking to marine depot so go to their site and search for "PFO reflector" if you want to research them.
Reflectors are not something you will want to DIY.