Here is what I said about the Kessils back in December of '15
"My early review of the Kessil A360We is this:
After having run Gen 1, Gen 3 and Gen 3 Pro Radions, I loved them. They were as advertised. They were controllable, customizable, and grew corals. I always like LED with T5 supplement, but I could not have been happier with the Radions. They simply didn't fit in this fixture. I wanted to try out Kessils, and my hand was forces, because no amount of modification was going to squeeze a 7" radion into a 5" gap between the T5 reflectors on the fixture.
The first and most obvious difference is ascetic. The Kessils are little cans, and they hang below the fixture. Radions would not. I actually love the look. I love the look of the three cans below the fixture.
The next most obvious thing is the shimmer. Wow. Everyone who has seen the tank has commented on the shimmer. I have never run MHs, so I cannot compare, but it is beautiful to see. I was afraid it may be too much, and it's not.
They are less controllable than Radions, which for some people is a good thing, as they don't want to tinker with their lights all of the time.
I do wish they would dim all the way down. They cut off at like 12%, which is OK, I have moonlights built into the fixture. But with LED, one of my favorite things is the slow ramp up/ramp down in the morning and at night. I don't have the replacement Kessil cable from BRS yet, so I am running them off of the Kessil controller, and it works fine. The Apex wizard is better. "
I had Gen 3 Radions on my old tank, with T5 supplements. I would love Gen 4 Radions, but that is a lot of scratch