The ATIs have slightly higher outputs than the G-man. I run the G-man myself because 6 months ago that was the best available. Then ATI and G-man were the same, and since have split... with the ATIs having a slight advantage.
I dont prefer the UVL superactinic... but many people do. Its one of if not the highest output actinic on the market right now... but it kind of cheats to get there. The actinic+ or blue+ bulbs are a blue shade, about 450nm, which is about 4x easier to make light with than actinics (as in, they have about 4x the output, and rival daylight bulbs even). Most actinics are duller, but thats because they are more purple, peaking at 420nm. The UVL gets away with being slightly brighter than the other actinics because if you look at it in comparison to other companies true actinics... you will notice it has a blue color... like they cheated. They used a slightly less actinic frequency that has a higher output. For many, this is fine though, unless you want the true actinic only.