In Australia and New Zealand I have seen TCL tv's being sold in stores for years, and it generally competes with the other Chinese branded type ones. We tend to get most of the big brand tv's here, we have the full range of 4k sony and LG tvs in most stores. We don't have Vizio, and Philips died out years ago although we had the ultra widescreen Philips models in store.
With the 4k tvs, although they upscale, I still can't say that i'm that impressed so far. And even the new sonys that can upscale slightly better, still appear to show a similar but subtle muira type effect. similar to what all the original HD Bravias had with backlighting issues, although not as obvious as it was 8 or so years ago.
And with commercial theatres, most tend to play 4k movies these days here unless a 4k version doesn't exist, and then it is obvious that you are not watching 4k. i'm actually pretty sure i saw monsters inc 2 the other day and it was definitely not being shown at 4k when i have seen 4k movies in the cinema before, was quite disappointing.
$1k for a 50" 2160p monitor can't be that bad really and you can really get it more for the resolution, and definitely worth the lower price and especially while content is very sparse. I've even heard the Sony tvs don't have any hdmi 2 spec or option to upgrade, so why pay a premium for a very uncertain future proof type product? It's like the first sony bravias. the X series had HDMI, the S series only had Component and VGA. I remember many guys on forums getting the S series, saying "HDMI will never take off that quick, I don't need it" .......Next models to come out all had HDMI....
now if it was a 4k Sony SXRD tv, then maybe it would be a bit of a different comparison.