Yeah I've tried spray color. It was pretty cool. It was a nice way to get an idea of what I would like like with golden blond highlights! Now that you've mentioned this, I may actually go back to that when I want a new look and try out some different colors. You can always just wash it out!
I have used colored hair spray twice, first time I did blue and second time I did purple and silver. It showed up very bright and vivid completely covering my black hair. It made my hair stiff and straw-like, but since I did it for a costume and didn't need it to be perfect I was happy with it. It didn't stain my clothes and it washed out easily (I wasn't CG then so I don't know if it comes out without sulfates). I don't think it's damaging if you just want to try it for fun
CG since 12/01/2010! 2c/3a thin BSL hair
Wish my hair was longer and fuller but it breaks off like crazy!