As long as you have good airflow I am sure it's fine. I like paint because of the reflective properties. It's much more diffused than silvery stuff and the spectrum from flat white is awesome. It REALLY brightens things up.

I would love to build a little PC grow case just to give it a whirl. It looks like fun.

Just think, if weed gets legalized ever these little grow boxes will be antiques with historic value. I almost want build one with a terrarium in it. It's just so freaking cool to have life contained in a little cell of an environment. Something about it geeks me out.