Interested in the new Retina iMac 27'' but I'm more than a bit concerned of all the threads I see popping up on forums about problems with the screen (yellowing, spots, build, etc) and fan issues. Is this so widespread that I should hold off until it gets worked out or something that's not as widespread as it seems? If it's something leaning more toward initial output QC issues, I can wait, but if it's more luck of the draw, hmmm...I don't know. Obviously if I got a new one and had issues upon unboxing, I can return it, but as I live in Japan (Apple sucks here), returns are not free, believe it or not. So I'd have to pay each time I make a return if it's a constant issue.