Just my 2 cents... We bought the pack of glow in the dark stars from the discovery store (others sell cheaper ones that don't work as well). I picked up some tacky stuff from home improvement store rather than using what's included. Stuck them all over the ceiling, some in groups, to similate the real thing. My boys love it, my husband and I love it. If they get tired of it, we'll pull them down.
Guess they might not look so real as one might paint. But, I can't say that I would spend money to have someone else paint my ceiling and then have to repaint it when it was outgrown.
Christy