I have all three, Dragons are by far the most complex of care because of the UVB, vitamins and calcium and consistent husbandry maintenance. I have three crested geckos in all bioactive enclosures and are by far the absolute easiest to care for. Room temps, high humidity and don't take up much space. My dragons are in a 4x2x2 (feet) each....my Geckos are in 12x12x18 (inches) and they are a hoot....BUT they ARE nocturnal. As is the Leo....Dragons are not....it is up to you but if you need any assistance I would help with anything you may need for info.