It really all boils down to YOUR APPLICATION. Closet growers and those outside the commercial world, don't buy paps.
Gavita has a much harder downward throw of light which would make it the more practical grow for a smaller grow. Now on a commercial grow the ePap is in many cases a better option. The real key here is the reflector like others have mentioned. For growers with no plant count restrictions growing large numbers of small plants (focusing on tops) EPAP IS HANDS DOWN YOUR BEST OPTION. The reflector is made to project a large spread (up to 5x6). While it does have SOME decent downward penetration, it's real strength is that it can illuminate an extremely large area very well. Don't get me wrong, I have seems seen some setups with TREES rocking paps doing very well. 3.4per light on a 60 dayer, that's not a typo. I've suggested to Lights Interaction on numerous occasions they make a "perimeter" reflector for lights on the side rows. The one (albeit slight) downside to paps is you are illuminating the walls on the perimeter of your grow rather than throwing the light down where you need it. The "side light" thrown is actually what makes the paps special on larger grows, except for on the outer rows. It may not seem like a lot but I'm about MAXIMIZING efficiency and production and any waste is still waste.
Keep in mind these setups were all originally designed for the Dutch market where small plants and greenhouse applications are the most common. These fixtures run hotter and need to be placed higher above the canopy than a traditional hps light. This is due to the fact again they were made for the Dutch greenhouse market that can accommodate for this.
I do agree with whoever said this test does not properly measure the capability and efficiency of these lights on large scale (with the majority of these lights being sold to commercial growers). It does however show the results of a single light in a tent... If that's what you're interested in knowing ;)
Wtf is a PL anyway?
