Anyone using >45" TV as a screen?

[xchaotic]

Lately I've been debating between getting a 4k monitor vs 4k TV.
Fortunately or not, most TVs start at sizes such as 49".
I've got enough space on my desk and I can have the screen a bit further but I wonder how big is too big, I feel that at 49" I'd be making some awkward angles just to see what in the corner of the screen?

 

[xchaotic]

I really like my current 24" 1080p screen PPI so if 40" 4k provides the same, I'll be aiming for this. My split is going to 80% work, 20% play so I need sharp picture with good enough colours and input lag low enough not to spoil the the 20% play. Can anyone recommend a particular TV model then?