You say plenty of solutions, if it’s not ASD, what are the alternatives?
Sorry for all the questions seems like a minefield. The Alienware one I would have probably gone for but burn in for productivity seems to be a real concern.
Well pretty much any monitor on the market will work, it just depends what you want to compromise on.
IF you don't go the ASD route then my own recommendation is pick up a good 27 inch 4k monitor. This will meet all your non-Mac needs and, in my experience, it's "close enough" in terms of pixel density/sharpness to the 5k Apple panel.
I had a 27 inch Dell 4k before I bought the ASD and was very happy with it. So unless you see a monitor side-by-side with the ASD the chances are you'll be perfectly happy.