Nope, but I run it at 100% scaling. I did notice that if the source on the TV is not labeled "PC" then the Mac uses YCbCr 4:2:0 and looks like garbage. Setting the input label to PC must send a different EDID because it seems to use RGB... On my Windows machine I can just override that in the nvidia control panel.
Oh well, will have to wait for the next MBP 15" refresh--don't see any real reason to upgrade yet to the latest TB MBP.
Plus, the @30 doesn't normally bother me, unless there's a solid large gray-ish color, which definitely shimmies.
These 40" Samsungs 4Ks really hit the sweet spot for Retina displays, at least for my old eyes. "Only" 1080P logically, but oh, so large and sharp!