I created a 3840x2160 cutout of a screencut of Cubase 7 and iZotope RX3 to take into shops to see what it would look like on various TVs, particularly the Sony 55X9004A. I included RX3 because it would really benefit from having as many pixels as it can.
Unfortunately, I did it as a .png, which wouldn’t work in the Sony, but it did work in the Samsung UA55F9000A, and it looked very crisp and legible, though the in-your-face retail colour settings were to much.
I want to use a 4K TV to replace both my two Dell 30"s and my current Samsung 40" TV. Ideally, I would like it to have passive 3D, which is optimum on 4K, but major manufacturers like Samsung and Panasonic make only active. LG’s top model is passive, along with the Sony 55X9004A. The latter has side speakers, but their model 55X8504 without the speakers is active. Que?
Also, the passive LG and Sony models are >50% heavier (33kg) than the Samsung (20kg), which makes a real difference when using a VESA mount.
Looks like I will have to decide if passive 3D, for the few times that I will want it, is worth the extra weight-bearing structure I would need to build.