These are the most durable socks I have ever bought. Wearing them out is next to impossible. I have many pairs of Cabelas Ultimate wear socks of this type that are warrantied against wearing out, but I've worn out every one of them.
This sock are also very comfortable, the toe-line seam is well put together and it's not prone to rubbing your toes. The only downside is the cost, but if they cost double what they charge, I'd still buy them as this is a fantastic sock when it comes to heavy-weight socks.