Quality of light is what Loup was speaking about....not quantity.....260watts of PC does not equal 260watt of T5 or 260 watts of MH.....T5 and MH cut through the water harder than other types of lighting. This can be seen with different wattages and heights of halides also, so your setup and depth of tank are key in selection and results you will see, keep that in mind......I have 14K 250s really close to the water, which I will bet are more intense than say a 10k 400W MH a foot higher.....I bet mine are more intense at the corals than the 400W 10k......its all about the quality of light, how far from the water they are for dispersion, and through how much water its got to punch through......remember inverse square.......
Kinda like Mike Tyson hitting you versus Michael Jackson 260 times.....are they equal?
VHOs are the old school bulb and T5s are the new kid on the block.....VHOs are a proven technology that has been tried and true for quite a while, but the market is drying up, so I doubt any new developments are taking place....however,the opposite can be said for T5s.....from what I see bulb choices and reflector designs are only going to become more plentiful.....that would have a lot to do with my deciding on a lighting system that I plan on using and growing with me as I do in the hobby.......
From the old school guys....ones that have been around more than 5 to 10 years........they say that the VHO still has the best "color" for an Actinic.....when used with MHs as mentioned.
I think space is a major consideration to look at...those VHOs are huge compared to the PCs or T5s......Depends on what you want them for....supplementation, instead of PCs.....sure then I might consider them......for daylight.....no way......the t5 is a much more efficient design that has a focused beam.......
If your really looking for the most intense lighting.....quit screwing around and up to MH......I would consider T5s for price of operation and heating concerns......if those aren't anything to worry about.....then go for it you won't be sorry!!!! Yes, Im a fan....of halides..and very biased, but only because I am completly happy with them.....I think you should go with one of those PFO or even the Aqualight Pro kits like I have with the Actinics and MHs built in....yeah little spendy but way cool with the shimmer and bulb choices when you have MH......literaly dozens if not a hundreds or so colors and brands that even vary from bulb to bulb by manufacturer.
T5s are a great option as far as a flourecent bulb goes, but let that not open the door into the others......because they aren't the same.....if your looking for the best lighting your choices are either T5 or MH......and you know which I would steer you towards...
I just saw my next tank tonight......240 cube with 1-1000watt MH on a light mover........now thats some lighting!!!!!
Not the featured tank, but another posters.(Reefer714),....check it out....sweet!!!
http://www.reefcentral.com/forums/showthread.php?s=&threadid=897075