I apologize for my English, but this is not my native language. I made notes during the tests.
I have Pimax 8k for 2 weeks. These are my first goggles, so the mini review will be from the novice’s point of view.
Previously, I had the opportunity to have a little fun with Microsoft HoloLens and Windows Mixed Reality goggles (unfortunately I do not remember which company).
After a long wait, I received the HMD. The packaging was slightly dented. Fortunately, the goggles did not suffer.
After unpacking I checked the goggles if they do not have any external defects — I did not find any.
The appearance is attractive, although I prefer a more rounded shape. 
There is nothing to complain about, because the goggles look modern, almost cyberpunk. 
As a four-eyes with a huge head, I was afraid of problems. And rightly so. My big glasses have trouble fitting into the goggles. They touch the lenses. When removing the goggles, the glasses sometimes stay in the goggles.
Fortunately, I have smaller glasses. However, if I tighten the straps, they can touch the lenses. I think it’s time to invest in contact lenses. Or look for and apply modifications that help for use of eyeglass. 
Soft straps are not a problem. They are comfortable enough for me.
Connecting the goggles to the computer and installing the software went without any problems.
I did not notice any dead pixels. I found dust particles under the lenses.
No problems with the cable.
Due to the weight, after a time 8k slide down on the nose. This causes problems with maintaining focus.
I do not want to tighten the goggles more, because I’m afraid of scratching the lenses with my glasses.
I will have to mount a counterbalance on the back of the head.
The SDE is slightly visible, especially when you look for it. However, during the game I stop paying attention to it.
The picture has a very good quality. High resolution and good color reproduction help you immerse yourself in the virtual world.
Thanks to the .121 PiTool version, you can adjust the level of black accordingly.
Some details are slightly blurred, but it’s the upscaler’s fault.
The text, despite the slight blur, is clear, the eyes do not get tired. Maybe small reading problems occur in Elite Dangerous.
The FOV is large, covering almost all of my field of vision. I can see the distortion and blackness only in the corner of my eyes. During use, I stop paying attention to them.
Comfort is good. Even during several hours of use, with small breaks, the head and neck do not get tired.
However, during long sessions, the face is slightly sweaty.
The gap on the nose does not bother too much. It can even be useful when you have to look at the keyboard. 
I tested the goggles on the GTX 1070 card. When setting a small FOV, the games worked well. Although there were some cuts and delays.
I also had the opportunity to check 8k with the RTX 2080 Ti card. On this card you can see the real goggles’ performance. There was no problem even with a large FOV.
I have not had the opportunity to properly test Smart Smoothing and Fixed Foveated Rendering. It seems to me that they work reasonably well. FFR introduces distortion to the image.
An additional difficulty in using goggles is the lack of a base station and controllers. For this reason, I am limited to using only games and programs that support the joypad. And for games that allow you to play standing or sitting.
Somehow I will have to suffer these few months. 
Generally, I’m happy with the purchase of Pimax 8k. In order to fully use their capabilities, I am waiting for controllers and lighthouses as well as other ordered / promised equipment.
Pros:
- nice image quality
- almost no SDE
- easy to install
- large FOV
Cons:
- problematic for glasses wearers
- dust inside
- sweet spot for the pupils is small