The LED lighting systems that are sold for Reef and Aquarium lighting do not usually produce UV-B. The wave lengths commonly sold start at 400nm and escalate from there which means that there would be no UV-B supplementation, only UV-A. The notion behind reef lighting is the brighter the better, and the spectrum in the range of 6500K which consist of all the warm colors to mimic the sun is what causes all the growth. So I do not personally think it would be at all beneficial to the chameleons, Reefs do not use alot of uv rays, and most coral prefer no UV Rays at all. I would stick with the commonly avail reptile lighting such as the linear 5.0 bulbs. I , Myself have personally been experimenting with Metal Halide lighting as a freat way to supplement my chams, and I am having great success they all seem to be very much more active and outgoing. I do not believe that a spot light and UVB/A lighting should be the only lighting implemented as the amount of light these reptiles receive even in the shade far exceeds what most keepers make avail to there specimens.