There just doesn't seem to be anything more comfortable than Swiftwick. Or any sock that lasts as long. The seven's seem to be the optimum height. Not too tight like a Giro can be, or destructible (shrinkable) as Assos, these are the right compression and composition. Probably why you hardly ever see them on sale and limited stock in the colors you may want.
After going back and forth with different brands Swiftwick has come out far ahead in comfort and durability. After years of rotating a few pairs there's hardly any loss of compression. There's no fraying or any other apparent degradation. There's just nothing negative to say about these socks.
Swiftwick is my choice for cycling socks 9 times out of 10. (DeFeet has some good ones). I've had this 7 in a merino for the winter and the Aspire in 1 and 4 because I'd rather have the air and sun on my shins. These perform marvelously just like their siblings I already own. Fantastic on your feet, no blisters, good breathability. Good compression. They stay up the whole ride. Opted for a Hi-viz yellow to add to a black kit for some added safety. I love the fabric. Really have nothing bad to say about these other than I wish they were cheaper. But then, I imagine they wouldn't be what they are.
I have a large collection of many cycling socks from several quality brands. I think Swiftwick socks are my new #1 choice (last three pairs have been Swiftwick).
Well made and comfortable.