I picked up 1/8" thick pieces of both Moonglow and Kirinite glow-in-the-dark materials to make scales out of. Although both were sold as 1/8" thick, the Moonglow is 0.164" and the Kirinite is 0.128" thick. As for the materials themselves, the Moonglow is more opaque and yellower (even accounting for the thickness difference).
This isn't to demonstrate actual brightness, as there are too many variables (end viewers' monitor calibration, iris dilation of the real-life viewer, etc). Rather, this is a comparison of brightness relative to each other over time.
I shot this at ISO640, 1/48th shutter, and on a 50mm at f1.4. Moonglow is on the left, Kirinite on the right.
Here they are after about 3 minutes of charging in front of the black light.
And then I shut off the light.
I also took an exposure at 5 and 7 minutes, but was limited to 10 pictures for this post. While they both look fairly dim in the last couple pictures, they were brighter to my darkness-adjusted eyes (with the Moonglow obviously brighter than the Kirinite). Even in a normally lit room, I can cup my hands over the two materials and peek in and the Moonglow has a noticeable glow to it while the Kirinite has barely any.
While I think Kirinite is offering some interesting materials and patterns, when it comes to glow power, Moonglow is the vastly superior product.