I agree with Mandark. I have a 55 inch Samsung that I got on sale which is 4K HDR (forget the HDR bit as it is not that good on the cheaper end like mine) the Samsung UE55NU7400 55 inch Dynamic Crystal.
The response time is more than good enough especially in Game mode and it has a PC mode.
You should be able to find some sort of deal on Samsung especially during black friday.