Samsung 40" 4K Ultra HD Smart LED TV

Would this make a kick-butt monitor for my computer?

Depends on what you do with your computer. A lot of media that doesn’t require intricate graphic details or insane graphics, definitely. If you need tight control over fine detail or if you game so hard you glow, then maybe not so much.

Honestly I don’t see the need for a 40" computer monitor. To be able to see it all, you’re going to need to set the thing far enough back that you’re better off just saving your money and getting a 27".