Single reusable value for post meta: Custom Taxonomy or Post Meta?

Suppose I have a post meta like “Region” it will contain values like “Region 1”, “Region 2” etc. But it should only contain ONE value. Also I would like it to have an archive page. If I use custom taxonomy, users can select more than 1 value. Is it possible to have a drop down type selection instead?

For mutually exclusive values use post meta. It is faster to read than assigned taxonomies too.

It is possible to create your own interface:

1. Set the parameter show_ui to false when you register the taxonomy.
2. Register a meta box where you print out all existing taxons with radio boxes.
3. Add a save action to assign the value to the taxonomy.

But in most cases you’re doing something wrong and misuse the taxonomy. 😉