Honestly, I see all these really really blue photos of M90 woofers when I first started collecting so I used to think there was something wrong with mine, but I’ve had over a dozen units cross my hands and never saw BLUE blue woofers. Usually they are some shade of gray, from very dark (almost black) to cloudy light. They always look really blue though, from the back side. I have a near new one with very little use, virtually no dust inside and no dust at all on the rear slats. That one was no exception, dark grey. So, a blue one would actually look a bit unnatural to me. Whether all were originally blue or dark gray, has already been discussed numerous times before so I won’t go there. However if I was presented with 2 identical M90s to buy; one with painted woofers and one with natural ones, I’d take the natural ones any day.