While installing my 6-IW's, I realized I wasn't sure what to do with the foam backing that comes within the speaker grills.  I'm assuming it is intended to remain in place after installation, but since I've got them apart while painting I started to wonder if it was merely a protection device while shipping.  I'm painting my speakers/grills so I'd probably want to try and brush a light coat on this foam if I'm leaving it in place.  Any feedback on the foam is appreciated.

 By the way, I'm initially very impressed with my Aperion speakers (first timer!).

Well honestly, all that is for is to hide the speakers a bit. With that in, you can't see the drivers as well. If you are going to paint the grills, I would DEFINITELY suggest taking that off, as the paint would get stuck on it give you quite the colored sound...

Thanks for the advice.  I ended up removing it during painting (that was kind of a no-brainer).  After 3 coats of thinned paint on the metal grills themselves, I went ahead and lightly brushed-dabbed some of the paint on the foam as well.  While I did end up with a couple of spots where the paint was probably too heavy (blocks a small portion of light when held up to the light), overall I am pleased with how it turned out and I don't feel the sound quality has changed much if at all, at least to my ears.

I did also conclude that the foam was intended to hide the drivers.  Honestly, if I were to do it again I probably wouldn't bother painting the foam, at least not until I saw what it looked like in place.  The speaker grill area is darker than my walls now anyway (using the exact same color wall paint), so the white background might have helped blend them in a little better.