Ok, I've read alot of reviews about these exOfficio briefs.  And all I have to say, is I'm not sold yet.  Yes, they feel great, and look good.  But they still ride up my thighs into my crotch when I am sleeping which is a real pain.  I am only 5'8" and 150 and 19" quads, so I am not an olympic weightlifter.  I have two pair now and both exhibit the same issue.  Sometimes they ride up while sitting or out walking, but that is more rare.  I will say I also bought a pair of the plain boxers by mistake (wife thought they were the same as the briefs), and to my surprise I like those the best.  I've also tried the REI brand and Jockeys' (Jock's don't ride up, but feel like spandex).  So buy them if you want, just don't believe all of the hype you read.