I love these boxer briefs because they are very comfortable, relatively durable, and they don't ride up your leg. These boxers also keep their shape after several washings. (I recommend using low heat settings for washing and drying these boxers because of the polyester content.) The reason they stay put and are durable is due to the fact that they consist of about 50% polyester (& 50% cotton).  One can verify this by examining the embossed label on the boxers themselves which indicates a blend of 50% Polyester and 50% cotton.  Unfortunately, the paper packaging of these boxers is misleading as to the fiber content. In any case, I recommend these boxers.

UPDATE (11/23/13): I have been using Hanes Men's ComfortBlendTM Boxer Briefs for some years now, and I have found them to be comfortable and durable for many washings. However, I have discovered that the grey-colored ComfortBlend briefs do lose their shape slightly. The other colors of the ComfortBlend briefs (black, blue, charcoal, or red) have retained their exact shape with numerous washings. I have taken a star off their rating for the grey problem, but I still recommend these briefs.