I'm 5'5", 145lbs and a womens size 8. I get the Medium Reg, bought a little over a year ago and will continue to purchase these! I use them on the flight deck of small ships, but I also buy them for my dad who works in a kitchen. These pants hold up to the heat, grease, salt water, oils or whatever you want to throw at them! I haven't noticed any color change, even after lots of work under the sun. I wash with cold water with all my other clothes with no problems. They have small rips due to the hazards of my job, but none of them seem to get bigger or tear in the wash. I expect to use these a couple more years and I will definitely purchase more in the future!