I bought the boys x-temp long legged.  Kiddo seems to like these a lot so I got them in 2 sizes.  Fits my 6 year old to about 1.5 inches above the knee.  He finds them comfortable.  They wash well; despite heavy use I don't detect fading over the period of a few months.  There have been no issues with the stitching and no manufacturing defects.  Surprisingly no holes in the material from use either!  So, I'm guessing the material and thread must be fairly tough while remaining, stretchy, soft, and smooth.