I use the T-Rex 100watt Flood bulb and it works fine. I actually prefer not having two separate light fixtures (one for heat and one for UVB). Its important that if you do get a MV Bulb, that you have a ceramic fixture w/ clamp or stand as these bulbs need to be angled directly down. I use an adjustable stand (found at most herp stores) which works out great because you can adjust the height which is critical with these bulbs. I also recommend a digital probe thermometer for accurate temps because these bulbs are very efficient in heating. So far, my Beardie is doing very well, eating and moving bowels daily, and her orange color is really starting to show now. Hope that helps.

Alex