they just didnt do much for me, but i go barefoot all the time. i would say the amount of benefit would be proportional to how bound up a person keeps their feet.
feet are supposed to be in contact with the moist earth and be earth temp - cool, like 45 degrees. thats when they are at their peek.
there is one other possibility with my experience - the pads could have been old or stale or something. they were the good japanese "gold" pads. or maybe they were the green. they were for heavy metals. shucks, i cant remember now, but i have them in the garage somewhere.