A couple of thoughts. I replaced the three stock WBGO POC TV's with supposedly better units from VIZIO. They do have a better picture but it was a mistake! Avoid VIZIO if you value being able to watch Over The Air TV or Cable (Campground) TV. VIZIO has implemented software that takes over easy channel search so that they can push ads. It REQUIRES a network connection to function smoothly, so if you don't have one, you're toast. You can search on Reddit for the many complaints about this. As it is, I've DUMBED the TV's (no internet connection) so that I can get OTA and cable TV when needed. If I want to stream FHD content (it's football season!), I plug my phone into the TV with an HDMI connector.
Second, I'm curious about why you'd want to upgrade to a 4k TV. Will you have access to 4K content? You'll need a download speed of around 50 Mbps to reliably watch 4K streams. FWIW, streaming a standard-definition (SD) show, you need a minimum of 3–10 Mbps. For HD videos in general, 10–18 Mbps is adequate for most streaming purposes. To stream in Ultra HD Video, you'll need 18–25 Mbps.
2021 Adventurer 29B | 2020 Chevy Equinox Premier 2.0T AWD Toad
It's Wine O'Clock Somewhere!