I will swap out chucks depending on what I am turning or sanding. I have used a plastic washer for years, and have noticed no wash/run out. I do prefer the chuck to be fairly tight, and mostly the turning pressure will continue to snug it up. The key in the chuck will get it off most of the time. The only time the chucks tend to get sticky is because of dust/chips/debris in the threads. Usually simple to blow out or maybe a stiff bristle tooth brush.
robo hippy