I have moonlight (single white LED in series) on both my tanks. Got them from Dr Foster Smith... cheapest. I have 6 over my 720 gal and 4 over my 200 gal, on timers.
I HATE THE BLUE... looks unnatural and gives me a headache. The white look much more like real moonlight .
Fish (especially the nocturnal guys) seem to enjoy it... I noticed DIFFERENT activity from different fish when the moonlights are on (as opposed to when regular lights are on or no lights).
But don't get the blue ones... does not look like moonlight, just looks like a blue light over your tank