Steve W. Berman and Jerrod C. Patterson:
iMac and MacBook owners have reported dark smudges and spots on the interior of the screens of their desktop computers as well as excessive slowness and break downs of their computers related to the lack of filter on Apple computers. The computer intakes air to cool its components, but with no filter, dust gets trapped inside. This affects the screen and logic board of the computer, leading to dust stuck behind the screen and gummed up motherboards, causing the computer to run slow and/or overheat.
According to many consumer reports online and across Apple’s support forum, the smudging substantially interferes with the functionality and use of the premium displays, especially for creative purposes such as photo editing, digital illustration and other activities requiring precise visual capabilities. The smudging often appears soon after purchase (but after Apple’s standard warranty period has expired).
When iMac owners raise the issue with Apple, Apple refuses to remedy the defect, forcing owners of affected iMacs to pay more than $500 to fix this screen defect, and even more if they wish to replace parts integral to the computer’s speed and performance.
I wholeheartedly support this, as my iMac had exactly the same problem. I sold it after having the screen replaced six times over a period od 3 years. Apple paid for the repair without question four times and I had to strong-arm them for the remaining two. I was delicately led to believe there would not be a seventh.
After an unofficial investigation in Poland, I found that every single iMac model since 2004 has exhibited this issue. Not every single iMac of course, but a decent percentage of every model. This has not been acknowledged or fixed by Apple since, nor are there are any repair programs.