Well, deffinetly not "The" QB, but the same style, flat pcb of mid-powers has been going strong as the drop-ceiling floro replacements since as far back as "15" that i saw remodeling a KFC.
Keep in mind, many lights, models, form factors & ideas come from the street, office & warehouse lighting industry.
It's making these type fixtures most efficient for growing that is the difference.
SK is a high-bay wharehouse housing. Flat pcb mid-powers were designed originally as floro replacements. Troff lighting ect...
Taking those ideas to the next level is what allows many growlight companies to keep it moving. There's only so many ways to deploy the photons.
I do not agree that it is old tech as the tech is in the diodes/driver which is always being updated.
Bar lights & Strips are not old tech just because BML made the Spyder 7 yrs ago.
As long as the design is providing the optimal coverage for its style then it will always be used.
