I've used one for years and love it for when I'm cutting a lot of strips the same width. I started out with a small one which caused issues as you had to fold the fabric in 3rds to get it to fit highth wise. When the longer/taller one came on sale, I grabbed it as I had cracked my old one at the corner. Mine is by Creative Grid, it's 20 inches long and 14 inches tall. Still due to all the slits, it's more flimsy so need to be careful when picking it up and storing it.