"He who marches out of step hears another drum." ~ Ken Kesey
I have those same tests with Magna beating all. Different shop, different results.
Would you mind going into more detail about your setup, how you prepped the ink (activator amounts, any additives, etc), what you tested on and how (mesh counts, dryer settings, etc)? I was really hoping the Magna would perform better, but it is just bad. It doesn't seem to have enough solids count/concentration, and didn't fully activate or activate as strongly as the others. Honestly, it acted a lot like a 50% Matsui Brite White, 50% Matsui Brite Base mix would act, both on screen and as far as the visible brown fibers were concerned. Did you add a higher percentage of activator or anything that differed from my tests?
The heat gun provides a perfect setting for the discharge process, tons of super hot, forced air blasting right through the garment. In reality there are few dryers that could achieve this, I imagine it's possible but the bill for running it would be insane, so it winds up being a compromise.
Your next test should be performance across a wide variety of fabrics. CCI is our DC White as it came out on top over the widest range. I think each of those inks you tested could beat the other two on certain fabrics. It's puzzling how this can be so different shop to shop. I firmly believe it has a lot to do with the curing apparatus. Try this test- fully discharge a test dot (ventilate while doing so) with a heat gun. Then run the same test dot through your dryer atregular production settings. Is the heat gun cured dot brighter? Then either your dryer or it's settings are not optimal for DC. The heat gun provides a perfect setting for the discharge process, tons of super hot, forced air blasting right through the garment. In reality there are few dryers that could achieve this, I imagine it's possible but the bill for running it would be insane, so it winds up being a compromise. DC being what it is I'm sure location relative to batches of shirt stock (did your Black G5000 come from the dye house in Country X or Country Y?), relative humidity, intake length of the dryer and planetary alignment are also factors.
For what it is worth, back when we did a comparison our front runner was the Rutland white. I could never for the life of me get the Matsui whites to ever work, they were always SO thick.
The Matsui NEEDS a good amount of water added, and printgen helps with penetration and printability as well. It is definitely way too thick out of the bucket.