What material were they playing on it though? At my local best buy all the 1080p sets display a standard hd cable tv channel, 7-8 mbps mpeg2 720p/1080i feed, while the 4K sets display pristine demo material at higher than 4k blu-ray quality with enhanced HDR footage. Perhaps Walmart feeds the same shitty feed to all tvs? I wish these shops were more honest and put a blu-ray next to a 4k blu-ray to actually see the difference. Then you can actually walk back and check at what distance/size it's worth it for you.

Guess my vision doesn't. Simple test on my laptop 15.4" 1080p laptop screen. I can tell that 1080p is sharper than 540p at 1m distance. Can't tell the difference at 2m, let alone 3m.

540p created by downsampling to 960x270, then pixels quadrupled back to 1920x540.
Top left, bottom right are at full res, Bottom left and top right are at half res. (Obviously open full screen, it all looks identical at 960x540)

But true the old chart is too conservative, this new one is a bit over the top.

The most expensive 4K displays at this Bestbuy each had their own unique demo reel, while the cheaper 4K sets had ads for Netflix, Hulu, etc. 1080p sets were playing seemingly random footage. One was what looked like a DVD of TDKR, and some of the others had TV ads running, so it could have been cable. Walmarts in my area tend to have the same footage showing on all their TVs usually with one special exception, so you may have hit the nail on the head, there.

I didn't realise cable was still capped at 1080i. 7-8mbits? Wtf? Does that include channels like HBO and Starz? Bummer, if so. I guess this explains why the Walking Dead looks and sounds so much better on Netflix than it does on TV.

The calculator on rtings.com tells a completely difference story. I need a 75" at 3m to benefit from 4k.

I'm completely blown away by the price of the TV I'll need for this

There is a benefit to 4k over 1440P on a 5" phone, even if you cannot actually discern the individual pixels.

It's a guideline, everyone's vision is different... And games aren't movies, there are other benefits to rendering a game at a higher resolution.

A 5" iPhone isn't viewed from 3m away.

Afaik hdtv broadcasts are still in 720p or 1080i. My cable box doesn't have a 1080p option, 1080i is the highest. At the start (2006) we got the full 15mbps channels, yet after they started adding more HD channels they reduced the bandwith to half to squeeze more in. It's something like this: Channels are received at 21mbps, it used to be 1 HD channel packed with 1 SD channel, now 3 HD channels are packed together and SD channels have been compressed even further. There's only a maximum amount of total bandwidth, more channels = lower quality.
If you know how big the HDD is in your pvr it's not that difficult to caclulate the average bandwidth. The more fits on, the lower the bandwidth gets.

And yeah HD cable looks like a joke during fast action scenes. Analog tv looked better during fast action. However analog has been axed completely to make room for more 'HD' channels. (You need a digital adapter now for horrible quality SD channels)

I guess I have to take their word. My monitor is $hit :)

The iPhone doesn't have a 1440P panel, let along 4k, but the same premise holds true.