wrenhunter@Totamarm to Feet socks are made for hiking, while these Darn Tough sock are meant for every day use. You could probably hike in these, but the F2F are designed to provide cushioning where you need it. @tot Farm to Feet also has a Lifetime Guarantee @wrenhunter. However, I have not tested it out. In general, synthetic fabric is much more durable than wool, which is why many companies use a blend of fabrics.
I know many people who have utilized the Darn Tough guarantee. There is a simple form you fill out online to include when you mail in your socks for replacement. The only stipulation is that you send back a pair of the same socks, not just a single sock. Darn Tough usually sends you a new pair within two weeks.