Be careful, it's quite easy to compromise the integrity of your helmet.
Certain paints can weaken the shell, as can sanding prior to painting. As well, I've been told that even a slight edge, as in a paint line, could catch and transfer crash loads to your neck/cranium. The finish can affect this as well.
Personally I think its a tad extreme, and I went ahead and painted my old SPH4 with Tremclad spraypaint from our local Canadian Tire Store.....but I doubt the crash worthiness was quite on par with what the original provided.
(.....some pious arse reamed me out AFTERWARDS when he saw the repainted helmet, but my "new" SPH5 has enough scratches already that I'd hardly be concerned about the affect a repaint would have)
Give Flightsuits a call, they'll give you the skinny.