They're not cheap, but less expensive online than at pet shops. I buy Power Suns, have been using them since 2009 with only recently a problem, but the pet shop where I buy them returned them and I got a credit for the next batch. I recommend them highly, they have higher UVB output than tubes, and supposed to stay strong for a year, at least that's what the warranties are for. I have 5 healthy adult male dragons & they've all been under Power Suns since 2009 and have all done very well. So I would recommend MVB. It would be better if you don't use a top on your tank and have the bulb in a deep dome on a lampstand, that way your dragons gets full UVB, but then I have adults, with low furniture and they can't get out of their tanks. It's different for babies. So that's my experience.