I used a 3/4 length self-inflating foam pad for tours of France and Spain. I add to the foot end of the pad with a folded fleece.
On my recent 6 week trip in N. Europe I expected colder and rougher conditions so I took the 3/4 pad plus a cut down piece of closed cell mat. There are several advantages to having 2 pads:
The inflating mat is a better insulator.
You can place one pad (closed cell) in the vestibule or on the grass to sit on. It gets a bit wet, scuffed up and dirty but you still have a clean pad.
Inflating pads can get punctures or slow leaks that are hard to detect. A closed cell will keep on working.