I have all three of the Astro metallic which ive been really lucky to get considering i only seriously began collecting mathmos lamps recently. For me the red is simply stunning and the best out of the three, purple and green both nice too but i find the green less vibrant than i was expecting but still looks good. I run mine on 30w reflector lamps like in the astrobaby's, they take a little longer to warm up but when they do they have a much nicer flow to them :)