Google didn't help me on this one... Wondering if the new lineup is PWM free? I see on the iFixit teardown for the 27" that it has listed a PWM controller, but I'm not positive that means it uses PWM and will have the issue. I am curious about the entire line, but mostly about the 27". Also, I'm sure there's been a lot of discussion, but if anyone could give me the quick and dirty on whether or not any GPU upgrade on the 27" is worthwhile? Thanks!