Some things to take into consideration:
1. If you want want to watch 4K stream you'll need steady Internet connection speed of 25 megabits per second or higher.
Actually they even have some recommendations on their site:
https://help.netflix.com/en/node/13444 2. There isn't a lot of 4K content out there
3. Check the reviews of the "smart" part of a brand before buying. From what I heard/was told by others Samsung is the best at this
4. The screen should be related to the viewing distance
5. Because of the human eye, unless you're sitting really close to almost see the different pixels of the screen .. 4K wouldn't make a big difference
I have a 4K curved display bought recently < 2 months (mostly because I needed a bigger TV + I liked the features that my old one did not have + there was a 50+% discount from Samsung for the 40" S9 model
)
- The curved display is great as it gives you more depth to the scenes. Check 2 TVs side by side if you can to see the difference (most obvious on sport broadcasts like a football match)
- 99% of the time I get to watch stuff that are not even HD ... so ... 100 more for 4K? only if you want to have that TV for the next 5+ years as I do IMHO
- the quality in HD is way better than my full HD LG that I bought 5 years ago. As Brati said... it's all about the panel and how it's lit not the max resolution
- as Winter said don't buy a huge TV if you're sitting close to it. I don't know how are the TV casts in Germany but at least in Romania there are a lot of TV stations that are not broadcasting even in HD ready. On my 40" sitting < 3 m away I can actually see the "square pixels" on these kind of broadcasts. There are calculators on the net for the optimal viewing distance as a reference.
- DON'T use WI-FI! The wifi on the TVs are usually far from great... I had a lot of issues finding the Wireless board specs for TVs. Most of those were not listed anywhere.
- The colors when connecting the PC are great now. On the old TV whatever was red was almost unreadable (like the WOT enemy icons) on the new one I don't see that issue (granted I only hooked up my Raspberry Pi to it and not the PC ... yet)