I have a nine-month-old Sony KP-57WS520. I opened the back up the other day and was surprised to see how the CRTs and mirror were pretty clean (only a few specs of dust). I was told afterward to use a flashlight at an agnle to see how dirty the CRTS really are (I didn't do this). How often do you guys clean your CRTs and mirror? I'm wondering if I should go back in and still clean anyway -- I forgot to look at the inside on the TV screen. Though if the CRTs and mirror looked pretty good, I assume behind the screen is probably good too.