Brett: "A good sock really meets three basic criteria: 1) blister prevention, 2) comfort, and 3) odor reduction. Smartwool's PhD sock performs admirably in all three categories.
First, blister prevention. We spent 26 days hiking and floating for 300 miles, and my feet were wet for 26 days straight. I only wore the PhD sock, and I didn't get a single blister, not even a hot spot. Googling variations of "best socks for blisters" the PhD Hiker appeared again and again. This sock doesn't keep just me out of blister-hell, whatever Smartwool is doing seems to be working for the masses.
Second, comfort. When it comes to hiking socks, wool is virtually mandatory. It dries quickly and is extremely comfortable even when damp or wet. In Alaska, damp or soaked socks for days on end are a guarantee. I don't sleep in my socks but this sock would double well as a sleep sock in terms of warmth and comfort.
Third, odor. Yes, it's a funny criterion but after a week of continuous use, this becomes an important one. A bad pair of socks can ruin the Feng Shui of your tent in an instant. Wool is naturally odor resistant and in a group of hikers all sporting wool socks, I think my PhD Hiker's do as well or better than the next guy/gal at keeping tent space livable.
Bottom line: these socks are durable, odor-resistant, and most importantly, keep the blisters down. Trust me or do your own google search. I'm not the only one swearing by them."