Thanks @NateCannaCribs. It’s always great so see the industry moving toward more evidence-based approaches!
If your question is to answer which ones are the most efficient, I’d simply be reaching out to LED manufacturers that appear to be on the forefront and ask them if they would be willing to send you a sample or demo fixture for 30 days, then box it up and ship it back. Shane from Migro (find him on YouTube; lots of great reviews) has a great working relationship with a number of manufacturers and does exactly that. His testing is done in-house and he provides a thorough review beyond just the numbers you would get from an integrating sphere, but not as accurate. Maybe a collaboration could be of benefit to everyone? He is located in Ireland.
If you’ve got other goals - which lights are the best bang for buck to the consumers, which of the lights your store sells have the best performance (for customers) and margins (for you), or something else - those goals should be well defined first. Lights for a home grower versus lights for a commercial grow are going to be tested for very different qualities.
This is a great idea that I look forward to hearing more about! The forum is a great place.