2 "black boxes run at 100% is the equiv (possibly more) than 1 250W metal halide bulb,ballast and fixture.
What is the cost difference?
You can get the Vipars WITH timer for $160 each.
Yea there is the white thing but that is sort of a choice.
2 Foot Giesemann Spectra 1x Single Ended Metal Halide by 4x24w T5 Fixture Use either 250w or 400w Single Ended Metal Halide Lamps. Metal halide ballast sold separately. BRS suggests the Luxcore Electronic 250w or 400w Ballast. Giesemann has been known for making high-quality light fixtures...
www.bulkreefsupply.com
A 24" using a 250w bulb is, ON SALE, $748 PLUS you need to buy a ballast AND bulbs.
Add $300
362 total watts w 4 24" tubes, 1 250mh.
Ignoring the 1.5yr replacement cycle for bulbs of about $140.
For most I suspect it is more in the 1 yr range.
equiv. to 1 black box every 1.5 years.
$1048 will buy you 6 1/2 black boxes
Total wattage from 400-750 watts depending on using some white to all the white channel.
Point is cost is relative to needs/wants more so than tech..