Deck. I've done pretty much the same, used a door mounted on a wheeled trolley with lockable casters. The door is removable usually hangs on the wall until needed. I've made all my tools movable in the same way on trolleys with lockable wheels (band saw, router table, table saw) and all at the same height so's I can use the table as an outfeed for all of them and push the tools I'm not using into a corner as my shop is quite small.
