When a dead reliable (at least mine has been) Khar CW9can be had for $350 or less I cannot see why...
Weight and size are the why. I have carried the CW40 as a holster piece, but I find it and its twin CW9 much too much gun for easy "drop it into the pocket and forget about it until needed" carry. Prints through most pants pockets and even sticks out a little from the top of a back pocket. And it is much heavier so causes the pants to want to droop etc.