You simply keep it if you like it, or find something else that suits your needs. Whether or not a new 4K LED rig would look 'better' will be in your opinion and that's what counts most here. Start looking around and doing more research. IMNSHO though, often the added resolution won't always mean much if you primarily watch a mix of content with different resolutions (especially any cable or sat feeds).
Personally, I find the need to find an HDTV with good response time a higher priority if I were a gamer than overall PQ. Watching movies is a whole other issue, and if that were your focus, keeping your plasma might be the priority. Truly, your Sammy plasma likely should be adequate for your needs since you aren't dealing with much content yet higher than 1080p.
Hello, I have a question about tvs that you guys might be able to help me out with.
I have a 50 inch lg plasma tv I bought in 2013. http://www.lg.com/us/tvs/lg-50PN6500-plasma-tv . That's the link to it. Idk if it'll work on here. I ended up moving back in with my parents, and put the tv in their living room. I'm moving out in a month. The thought was I'll take the tv and they'll go get a new one, but then, It was brought up about them giving me some money for it, and I'll get a new tv.
I hate buying tvs. There's so many factors that go into them. What I'm wandering is. Is it worth keeping my plasma considering you can't really buy a new one? I don't think I want to spend the money to get an oled tv. Would the picture from a uhd tv be better than my plasma? I do have a ps4. So I play games a lot. I would want a 60 inch and I don't think I'd want to pay more than a grand. I looked around and couldn't really find any posts about this topic. Let me know what you guys think. Than you.

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