I tend to use a lot of frost-proof glazed ceramic pots for my collection of maples and conifers. They are not inexpensive, but they are excellent for longterm use in the PNW and you can color coordinate to the plant in question or the garden design as a whole. I have a few that are into their second decade in my garden.

Because I do a lot of professional container plantings as well, I often recycle a lot of clients' old containers including a bunch of larger plastic resin containers that look as though they are cast concrete or carved stone. If you've priced these recently, you know they don't come cheaply either. And these over-sized plastic pots are ideal for some of my more mature plantings. Wood is also an option, but doesn't last very long, even containers made of cedar, redwood or oak wine/whiskey barrels.

I avoid terra cotta, black nursery pots or the cheap plastic pots available at discounters - they just won't last in winter or do overheat in summer.