I have to be honest, I really don't get the appeal of this. However, I ordered it for my son and he swears it really helps and that is all that matters. We were considering medication to help him, but this does the trick.
It does fit snugly under my toilet, so it's not in the way. I think that the taller version would have worked better for me since I am very short. My legs just don't squish up the right way, I think.