Well, last time I checked some of the Mega Rays and T-Rex Active Heats had been causing eye issues, and I heven't heard of them being completely fixed as of yet. I don't use those though, so I could be a little outdated with my info LOL, but last time I heard they weren't perfect yet. With the Exo Terra Solar Glos, I do believe that the problem with those is that the UVB output gets weaker really quickly. ReptiSuns have never had any issues, and my beardies along with many others have always done great with them.
The vitamins I was talking about weren't D3, there is a seperate vitamin/mineral powder that you should have for beardies.
And since the flourescent tube UVB lights aren't strong enough to allow a beardie to produce their own D3, it's usually recommended that calcium D3 is used with those. If you are using a MBV though, you are right that you don't need additional D3.