ive had my Late 2013 iMac for about 5 months now. i bought it from ebay used, in like new condition for £1500, it came with the apple USB Super Drive, Magic Mouse, wireless Keyboard, Magic trackpad. it was about 11 months old at time of purchase. it is also a fully spec'd out iMac pretty much. but after a day of use i experience the image retention error, other than this problem I'm very happy with the iMac.. but i wondered if anyone had a solution to avoid this problem? the one i have used has been; keep brightness at exactly half way or 1 block over half way or less. when i do this i never get the image retention. if i turn it up brighter and keep it at that brightness for a period of 5 mins or possibly less, the image retention kicks in. i wondered also why the image brightness in my case seems to be the cause of it happening? does anyone else have the same problem? I've never complained to apple as i know their stance on it, but it is my intention to do so at some point to see if i can get a new screen. also.. i noticed this slim unibody iMac has a much looser tilt mechanism than the 2009 iMac we have downstairs. its just about bare able. it will usually tilt a hair low from a bit of movement but usually it stays straight. however if i wobble my desk or jump in the room the chin will certainly go way down at an angle away from me. does apple improve this? or is this acceptable behaviour of these newer imacs?