I've just been using it and I like the scope mounted one because whenever I lay the gun down the pellets can't touch any surface the gun is laying on.
As Doug said, it holds 16 pellets. I tried some other hi density foam I had, but the 1/4 inch thick pipe insulation is just the right thickness and density to hold, but still allow my fingers to push in the foam and grab the pellet skirts easily.
And this 1 inch pipe insulation is just the right inside diameter to rotate it with one finger and it will stay where I stop it, so that when partially full, where the remaining pellets are doesn't fall down where I'd have to spin it back up to get to a pellet.
Thanks again,
Paul.