The differences you are seeing in the photo is based on white balance of the camera (4500k)
the LED that is a higher color temp than the white balance, looks whiter, bluer, cooler
the LED that is a lower color temp than the white balance, looks browner, yellower, warmer
There is no one True White. It changes based on how closely the LED color temperature, matches the white balance of the users brain at the time.
People who have been in the sun, have their brains auto white balance set to 5500k, so they will prefer 5000k led to 4000k led, at that time. Myself included.
otoh, people who have been sitting under incandescent light (3000k), and whose brain has auto white balanced to that color temperature (takes over 30 minutes for our brain to lower it white balance), will prefer 4000k instead of 5000k, because the 5000k will be too blue.
If Im working on a car in the sun, I prefer 5000k (or even 6000k), and hate 4000k
otoh, my home lighting is 3000k, and when my brain has had time to white balance itself to that color temperature, I HATE 6000K (AND 5000k), and I much prefer 4000k.
I notice that I like my flashlight to be close to, or slightly above the CCT that my brain has adapted its white balance to.
When I wake in the dark for a toilet run, I prefer 3000k, find 4000k too harsh, glaring, blueish, and I wont use 5000k or 6000k at all.
The rule of thumb is to choose a flashlight that is not warmer than the white balance of the users brain at the time.
since I actually seldom work on cars, my need for 5000k or 6000k is rare.
since I live under incandescent light, when I use a flashlight at night, I find 5000k or 6000k unnecessarily cool, and prefer 4000k, so I usually buy 4000k more than 5000k, but I like to have a range of choices for the different environments and ambient light situations I use a flashlight in.
Since the majority of my use is at night, if I had to pick 4000k or 5000k, I would go with 4000k.
But if the majority of my use was during daylight, I would choose 5000k.
What I actually do, is I edc 5000k during the day, and 4000k at night.
on my nightstand is a 3000k light, that I prefer when I wake in the dark. I dont usually edc 3000k, because it is not as versatile as 4000k.
I edc 4000k more often than 5000k, because most of my use is at night, when Im adapted to incandescent.
choices are good. It is useful to carry a flashlight that is not warmer than the white balance of my brain, at the time of use.
when I use warmer light, I also tend to use lower lumens, and when I need higher lumens, I tend to also be using cooler light.
So, I would buy a 4000k Samsung, and a 5000k Samsung, both in 90 CRI. I wont settle for Low CRI, at any color temperature.
Low CRI, and also low R9 CRI, make reds look brown.
It is easy for low CRI to illuminate green and blue things, those are not a challenge for an LED. The Challenge color for an LED is RED
which of these two red things look more brown:
the top one is more brown, it is the 5000k. That tells me the bottom light, 4000k has more CRI, or more R9 CRI (the saturated RED portion of the CRI indexes)
However, both of those lights are 80 CRI, and both could do a better job of showing more Red, and less brown