I too sit about the same distance from the screen and it is raised so that the center of the screen is on my eyeline.
I take your point about taking in the 'whole' screen in detail, but what what is particularly useful for me is being able to see a life sized screen render at a realistic viewing distance for a 'default' A3 sizing, and not have to scroll the image on the screen to examine it.
As regards George's point about about opening multiple windows being easier/more usable? on the larger screen... I'm afraid I am one of those people who gets frustrated flipping between multiple windows.
I prefer to run a secondary 24 inch monitor to the left of my main screen and park Photoshop panels etc there.
Additionally, I have an 'old' 27 inch (sRGB) monitor to the right of the main screen which I keep in portrait mode, which I use for web browsing, and very occasionally to display images in portrait mode. I have a feeling that when either of the secondary panels shows any sign of failing I will look to replace it with a fully RGB compliant 27inch screen and set it up in portrait mode. (Though I expect this is not likely to happen soon!
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