No. Basically those numbers mean nothing. God knows how those companies figure out those numbers. Has the reptisun 5.0 been working good for you? Why switch if it has. I use either the Repti-sun 5.0 for some cages and Zoomed Powersun mercury vapor bulbs for my others. These have worked great for me, and others for a long time now.
With the fluorescent like the Repti-Suns the dragon has to get close to the bulb to benefit from the uvb light. The dragon has to be closer then 12 inches to the bulb. So for some setups these work fine.
Some of my cages are 2 feet high and a 12 inch high basking spot is just to difficult to get. So I go with the mercury vapor bulbs Powersuns. With the mvb they give off stronger uvb and throw it farther. So for my setups being 2 feet high. I only have to raise up their basking spots to achieve a desired temp, not to reach the uvb. In my opinion I think the mercury vapor bulbs like the powersuns are the best over all. More beneficial uvb and at farther distances. If you use fluorescent lights in my opinion Repti-Sun 5.0 or the Iguana lights are the best choice for those.
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Mystical Dragons