This synthetic paper has made the best endpapers we've ever used. It's tough, durable, and resistant to buckling.
We are now out of stock in the larger size and have only limited stock left of the A3.
We generally use this for making the endpapers for hardcover books of any size. The direction of the grain is not crucial with synthetic paper, so you can fold either way for good results.
The paper can be easily cut with a craft knife and a straight edge, such as our 500mm stainless steel ruler.