My husband was a general contractor for 20 years by the time I met him.  I discovered these pants one day when we were replacing his work boots.  He was very skeptical as he had worn Levi's to work for over 20 years.  He has been a convert for the last 5 years.  Loves the light weight knee pads that can be slipped into the legs and all the pockets since he is always kneeling down and would otherwise have to wear the strapped on pads. His 2 sons and workers wear them now too

Update: Need to add that although these pants are GREAT, the knees tend to wear out very fast. My husband is a builder but has his hand in everything so he is sometimes on his knees a little and sometimes a lot but has the pads in all the time.  The knees wear out way faster than any other part of the pants.  I'm going to try the washed duck to see if the knee wear is better