Cool, always nice to hear about people buying expensive stuff and testing it for us!
I assume you're driving it with DisplayPort or you'd be stuck at 30Hz which is a bit slow? I take it that this Samsung is a good quality TN panel?
I did some size calculations and my current Dell P2414H 24" screens have a 0.25mm dot pitch while your 28" 4K is 0.17mm dot pitch. Which is way too small for my eyes. But in a few years I might consider a 40"/42" 4K TV which would have the same dot pitch as my current one. Hopefully by then all OS will have more than Windows 7 Win+Cursor key combination since such a monster screen is equal to four of my current one and I wouldn't want to spend all my days resizing Windows. (Not that I have tested Linux since I started using two screens.)
For my idea of a 40"+ screen I would only consider IPS or VA since at that kind of size horizontal viewing angle limits would apply even straight on.