I used to have 3 kessils and 2 400watt halides but it would blind those sitting on the couch, you could feel the heat from 3-4 feet away
This just made me giggle... lol... But gets the point across about which lighting is more like the sun...
Totally agree LED's have plus sides with small form factor and less heat (usually). My frag tank and coral qt are pure led for this reason... My nano is too... But that is about to be switched out for a 50 gallon because the corals have out grown it.
Having run both LEDs and t5's--i will say that for my main displays--i just bought to two chillers on sale at marine depot...
For main displays of any size past 40-50 gallons, I think i prefer to have idiot proof lighting that grows better and bigger and faster. I'll just run a chiller and install a canopy or hood... Lighting is then just one less factor to worry about...
The main reason is stability. Big growth i think means healthier coral. Growing quickly seems to soak up nutrients quicker and less algae issues. T5's definitely gets corals to size quicker and then pests and disease are less of issues--big growing corals survive most anything--but slow growing frags do not.... And when the corals grow quickly you can frag for back ups.... I have some corals under LEDs that just don't grow or grow super slow, while others grow great.. LEDs have been weird like that for me.... The same corals under t5's thrive... so i like the simplicity of something that works...