There are various brands of compression socks out there! It depends on your needs really and if you're able to get a good pair measured for your needs, it can be quite a boon for you, tbh. I had an EVLT done for my Varicose Veins and took to ]wearing compression socks under the doctors advisement as apparently it aids in faster recovery to EVLT and such treatments!
Just know that there is a bit of a time period that you may need to adjust to it completely. Once you've completely adjusted to it, it's all good.

I wear them on long flight and use the brand Compressport. Its for athletic wear post exercise (or during if you are a triathlete).

Helps me feel a bit fresher since I probably got a workout in before the flight and when run when I land.

I also wear Sockwell compression socks at work and for flights - they do make a difference without being uncomfortable. I have the medium compression, and I bought them from Amazon (they have plain black if you want them for work). I was a little worried about the brand when I first bought them, since they're not one of the "top names" that athletes etc use, but they are pretty comfortable at a reasonable price, they wash/dry well, and they are holding up to wear and laundry. And, FWIW, I am overweight with big calves, and they still fit without being uncomfortable :)

I use sigvaris. I get cotton(68% cotton) and socks are very comfortable. I have navy pair. Like the idea of having a choice of more than black or white.

I started using some after some surgery I had recently.

I was speaking to my surgeon about flying etc and he said I should just keep the surgical socks and use them for flight socks as they are better than any you could buy on the high street.