Icebreaker made a change to these and made them out of slightly thicker material. IMO, that was just the right change. They now have just the right amount of substance where they hold their shape around the legs all day. Just got them so can't speak to durability, but the previous thinner version ripped pretty easy (as mentioned in other reviews).
I've learned my lesson about buying great feeling/fitting clothes. Manufacturers change designs pretty quick to either meet bean-counter requirements or to just be different (although in this case Icebreaker has made a better product). I'll give these a go for a few months to get an idea on durability then probably purchase quite a few more.
This review was written in the old system and had content requirements that are different than reviews written today.