doadster,
light is a very personal subject,and it all comes down to personal exp and what you "like" to see
example Icefire, by looking at sig he lists 4 T5 and thats what he/she is recomending you, in simple terms he/she is recommending what works and likes in his/her case.
here you will get some info, but I would do a search, and learn more about lighting, and at the end you will find that you can do a sucessful tank with pretty much any good light currently on the marktet, either metal halides, T5, VHO (T12), PC ect.
hellolights is also a great place to get lighting equipment, very knowledge personal, and have
"30 Day Policy - Unconditional Guarantee"
call them and talk to them, should help.
I personal like light Metal halides of the lights forms currently available, for two reason,
-shimmers
-sps
if I want alot of light and have a problem with heat and want sps, I would do T5
but for a soft coral tank, I personally like light VHO, think their actinic is still the best and they are cheap and don't mind changing them once a year, I like their overal colors
for a 90g soft, 4 4ft with the few combinations available that tank will do great, on the lighting department
you can put together at hellolights the whole lighting setup with bulbs with internal reflectors ( 4 footers, S220 ballast) for about $200 if you like DIY, and hellolights will help with any question, as we would too, and I think is pretty easy to assemble
S220 VHO ballast link to Hellolights
a few links to get info and look at some tanks
VHO only reefs
Let's see pics of VHO only tanks!
Anyone using just VHO's
good luck on your search,
sam