You're both on the right track. Like I mentioned, if you can get a 4K TV now at a really good price (as in, what you would pay for a regular 1080P TV), then go for it.
But, the more important specs are always gonna be contrast ratio and black level/color reproduction. I'll get to that in a second.
4K / UHD
As for viewing 4K+ on your TV, there is a diminishing return. Human vision resolution is finite. Basically at a certain point, from a certain distance and size, your eye can't tell the difference between 1080P, 4K, 8K, or higher. (The go-to example is to sit on a beach. See how many individual grains of sand you can count right next to you. Then down by your feet. Then 20 feet away, etc. Now imagine those are pixels) So there are only two realistic applications now and in the future that 4K actually makes sense for:
1) Putting a 75-80" TV in your living room or home theater. Which is doable. Most people won't want that behemoth in their main living room, but if you've got a basement or your own place where you've got all the space in the world and that's where you watch basketball and movies and play Xbox, then 4K could be nice there,
if you're sitting close enough and your TV is big enough.
2) Sitting really close to your screen, like a computer or a tablet. This also makes sense. A lot of people are watching TV, movies, and playing games on computers and personal devices, and you're usually only about 1 or 2 feet away. So a 27" 4K display on your computer that you sit directly in front of is a pretty decent picture too.
As for 8K, there's literally no advantage for you as the viewer because unless you put your nose on the screen, you'd never tell the difference between 4K, 6K, or 8K. Shooting in resolutions higher than 4K makes a lot of sense on the production end because it gives you more real estate to crop in, reframe, do roto and matte painting, etc. But in the end, you'd just down rez to 2K or 4K for the master. From a viewers perspective, if anyone ever starts marketing 8K to you as something worth buying, they are ripping you off. 4K is already pushing that boundary.
BETTER PICTURE QUALITY
If you really wanna see an improvement in your picture, you'll be much better off putting it toward picture
quality over picture
quantity.
The most important things to look for in your TV are contrast ratio and how it handles black levels and color reproduction, and Dynamic Range.
This could be a whole other thread, but think of it this way. Imagine you're watching a widescreen movie on BluRay. One that has the letterbox black bars above and below. Basically, on your cheaper TVs, those black bars are gonna be kind of a muddy gray. On a really nice TV, they will be pitch black.
Now extrapolate that idea to the actual movie or TV show or game itself that you are watching. The best TV's show the deepest, richest blacks and the brightest whites (and here's the important part)
without losing any detail in the picture whatsoever. That sounds like a simple concept, but most TV's aren't good enough to do this.
It's easy for TV manufacturers to cheat this, and they do this in every Best Buy or Walmart you've ever been in. They put TV's in a mode called Torch Mode, where they crank up the contrast settings, crank up the saturation settings, and make everything look a little more blue. So to your quick eye, they look all bright and poppy. But what they really did is crush out 25% of the picture detail.
Think of it like this. Say you're watching The Dark Knight on Blu Ray, and you're watching a scene with him in the batcave. On a crappy TV on torch mode, the blacks will be real black, the whites will be real white, but the cave walls will just be totally black, the computer screens and ceiling lights will be mostly pure white. On a good TV with a good contrast ratio, black levels, and dynamic range, the cave walls will be as black as they need to be, but you'll still the water trickling down them, and his black capes hanging on the wall. You'll see all the detail in the computer screens. You'll see the light fixtures and bulbs around the lights, etc.
Here are a few examples that kind of get the point across. First, on the left is a TV with bad contrast ratio and low dynamic range. On the right is a TV with good dynamic range and contrast ratio. See how the blacks are rich and dark, but you can stilll see the details in the shadows on the stripes, in the whiskers on his nose, etc.
Here's some more that kinda get the point across. It's best to see it in person. If you want a low pressure way to see nice TVs in action, go to a Best Buy with a Magnolia Home Theater section. I know the one in Fairlawn has one. All those TV's will be higher end and tuned right.
Also, here's a really great article about filmmakers and creative pros who are way more excited about improvements to Dynamic Range way more than 4K.
http://variety.com/2014/digital/new...tv-but-more-to-high-dynamic-range-1201154367/
So basically, look for a TV with a great quality picture rather than one that outputs the most pixels. At least for now. In 5 years, every TV will be 4K. But until that's necessary, just get the best looking picture you can afford.