I recently bought a large foldable, and I was sceptical at first, but it turns out it was really practical. Now, I can have a small cutting mat for when I do small work with few parts, concentrating on a smaller area, but I can also double the size when needed.
Might seem like an unnecessary thing but it is crucial for me since I no longer have a workbench; all my building takes place on the dining table. And nothing can go on the dining table, so I have to fit everything more or less on my cutting mat.