They are super smooth, glide around easier, provide about 95% of the time great control of my package and I get no chafe or chub rub.  This is the second pair that I have purchased and I will continue to get another 2-3 when I feel like spending the money.

Update after 3 months of use.
These things are literally the best things to cradle my junk... ever.  No offense ladies ;-) After getting the size right (I had an XXL, an XL, and a L... Im 6'4" 260lbs with a 42" waist and a sizeable rear) and I settled on the XL being the best fit for me when running was involved.  I bought another 5 pairs.  I never thought I would spend so much money on underwear, but as long as these things are for sale, I will continue to buy them.  I see no fatigue on the ones I have used so far and I have been using them 1-2 times per week every week for the past 3 months (since I only had 3).  I machine wash cold and air dry.