Hey I want to get myself a new iMac late 2015 i7 4ghz 32ram fusion or maybe ssd. I know that previous models had a few issues with heat and with certain conditions created cloudy marks on the screen corners ranging from dark to light grey. My question, does anyone know if the new models 2015+ create this issue too? Has this issue been addressed? I hate to spend 4000+ and then this issue appears. My 2011 iMac has these spots and I never repaired it cuz I had no warranty and it was too pricey. Any tips would be helpful please. Thanks.