The Smartwool PhD is a high-performance, fitted merino-blend wool sock that earns a notable mention for comfort and versatility. It is best worn alone, a bonus for minimalists, but a fact that might dissuade buyers accustomed to a dual layer sock system. The PhD is ultra-versatile and comfortable in almost any conditions except for the extreme cold, similar to all other socks tested. We brought it everywhere with us during this testing period. It fits both men and women well because of its compressive paneling and fitted design. There are women-specific options available.
We love it for hiking, trail running, backpacking, biking, bouldering, and more. In all conditions, it performed beautifully. While other socks might claim a specific advantage, this sock is all around versatile. Its most significant competitor was our Darn Tough Hiker Full Cushion, our men's Editors' Choice winner that won for its ability to breathe better. We also appreciate that it was much more durable than the Smartwool PhD and comes with a lifetime guarantee. However, it doesn't compare to the level of comfort that the Smartwool PhD has to offer. This is a fantastic sock, and a notable mention because of its great performance across a wide range of conditions.