Amazing socks! Swiftwick is the only brand I've purchased in the last three years. They're on the expensive side as socks go, but running 16-25 miles most weeks, they are worth the investment for me. Other than damage caused by my dog, I haven't experienced any durability issues like I had on a couple brands I had tried previously for merino wool socks. I'm bummed that that seem to have discontinued the Pursuit Two shortly after I snagged a 3-pack. Two inches (quarter-length) is my ideal height, and I don't see myself going back to Pursuit One, so it looks like Pursuit Four is in my future.