I have two beardies and both are in 55 gallon tanks with the Reptisun 10.0 T5 HO 46" lamps. I've been reading around the site today and it seems that with this kind of bulb with this size tank most people recommend a 22" bulb.
When I got the original one for my first beardie, York, I just wanted to make sure that no matter where he went in his tank he'd get good UVB. When I rescued Stimpy I felt that it was extremely important for him to get good UVB no matter where he was in his tank since he has a pretty bad case of MBD.
I guess my question is, are they going to be OK with these lights? I'm beginning to believe that I could have spent a lot less on their UVB lights, but is this a case of too much of a good thing?
As long as you have them far enough away or enough cover so the dragons can self regulate it should be ok. With UV coverage for the whole tank you want a lower level than if you have a focused nice bright sunny spot. You can use height, mesh, fake plants, etc to help build a gradient.