Yes, bluray disc players do their own up-scaling (resolution enhancement) and they're pretty cheap now. However, you can't buy a 4k (4000 vs. 1080 original Hi-Def) for $15. However,they are getting cheaper by the year.
I'm sure many manufactures have great 4k sets. I just can't imagine any others have a better picture than our 55" and 65" LG displays. Like I said above, it's like looking through a window.
That said, I've read 8k is now the next thing. I don't believe you will be able to see the difference on a 55" 4k TV. If they can make projectors in 8k resolution for our 110" screen in the theater to replace our older Pioneer projector (480 widescreen), I'd be interested. I now have a 65" 4k sitting in front of that screen. Do you know if there are 4k projectors as of now? I haven't kept up. If so, I may consider it and go back to our 110" screen in the theater. Yes, we have the distance for such a large screen in case you're wondering.
Plus the theater audio surround is incredible. Besides the 200 watt receiver, we have Def-Tech towers with powered adjustable subs (on side of tower) in front and Mirage towers in back for surround. All 4 have matching mid/tweeter speakers in front and back, except for the center Def-Tech.
With the right adjustments, the speakers bouncing off the walls is like being there live. The depth, width, and rear sound reaching a millisecond later than the front speakers is like being in a concert hall, or club, or any venue you desire according to your surround settings. They also work wonders for movies. I will never go to just front facing speakers again. Check out Definite Technology speakers.