Research chinese black box. They are all the same. Mars aqua, victraspect, etc.... 300w Chinese black boxes
Not entirely accurate. Many so-called black boxes, including Vipars, Mars Aqua, SBreef, etc., have different led layouts/spectrum, drivers, cooling, and overall build quality...some better than others.
The 3 listed are the better quality lights. There is also a slew of other Chinese lights being sold on eBay, some of which are fully wifi controllable, but I have no experience with them.
The biggest draw to these lights comes from price (especially for new reefers with sticker shock), ease of use, repairability/modding (leds are easy to replace change out to a different spectrum), and they grow coral... Arguably as good as a name brand led fixture though I don't think anyone has actually done any long-term testing, I'm going purely off of anecdotal evidence (pictures of people's tanks running black boxes here on R2R).
Now, it's not all rainbows either. You give up some controlability and the leds aren't exactly top bin Cree/Luxeon etc. and will likely fail prematurely (2-3 years most, UV will fail earlier) and the drivers are no-name.... Not exactly Meanwells.