Never tried it, but you should try just to see if it would be a good option for you. I am in zone 9b and I left the majority of my echeverias outdoors during the winter. I left them in their container plantings, had the containers banged up against the house under the eaves and put a frost cloth over them every nite. Our lowest temp was 29 degree F but I assume you have lower temps and more moisture in WA? You can always leave one outside in a protected area and leave one indoor under artificial lights and see how it goes.
