That's what I figured due to the low price. Thanks for the info, I'll stick with powersun. Maybe the nat geo mercury vapor would be better for lower uvb needing reptiles. Has anyone ever tested one using a solar meter?
I have not, but I think others on the UVBMeterOwners group on yahoo have if I remember correctly. I have however tested the Zoomed MVB, and would recommend instead buying the MegaRay bulb. The MegaRay was around 2-3 times better, and only a few dollars more. Plus it lasts well over a year, and the ZooMeds typically closer to 9 months.
I just picked one of these up for testing. Will post my results in a few days. It does have a cheap feel to it coming out of the box. Gives off a dull blue glow and isn't putting out much heat at 14''.
Sorry for the delay on this. I tested the National Geographic Solar Heat last night and thought I'd post my findings here for future reference. In general, it looks/feels like a cheap bulb. I wasn't crazy about the UVB output and there's no way it could be used without a secondary heat source even for an adult dragon. I noticed a significant dropoff in UVB output after about 8'' up and 8'' out from center. I ran it for about an hour before taking readings to make sure it had time to warm up. There is a 160w version available that may produce more satisfactory results but I only have the 125w available at the moment.