The large one is a joy. I remember when I started out with these, I have all three sizes, I could not get the small one in at first. Now I can insert the large one with ease. I am just now getting the next size in, which is only 0.5centimeter larger in circumference. They do feel like a perfect fit, thanks to the shape. And they are staying in fine.
For those who are interested I have he measurements:
small = 15cm / 5.9inch circumference, 4.8cm / 1.9inch diameter
medium = 19cm / 7.5inch circumference, 6.1cm / 2.4inch diameter
large = 22.5cm / 8.9inch circumference, 7.2cm / 2.8inch diameter
At first it is hard to insert these, but once you find a way to get started then it will go easy. I hold the ball not centered in front of my butthole, but more like as if I am at the bottom part of my butthole, then inserting the bottom first then working up to the top part. I know it sounds weird but that's how I manage to get them in easily. My butthole is not a nice round circle but more like a slot.(aka pussy style)
Next one up is the ace of spades, 24.5cm / 9.6inch in circumference. Nope doesn't fir yet. 😃