The Belmont has long been one of my favorite Filofax binders. They do not have stiffening, are made of the most beautiful thick, flexible saddle-type leather with distinctive, classy stitching. They wear extremely well. I have the complete collection but have three tan A5s. They are extremely hard to come by.
This one came from eBay and is in a box (oh the luxury!) and tissue paper (ditto!) plus has full inserts.