Yeah, that's a good way of putting it. Seems like the supertips don't conform to the shape of my ear canal very well, because even when I have them in and in place, they're still letting a lot of sound in.
The tips that come with the Coppers are quite a bit more rigid. The Sonys are really soft and they mold to your ears pretty well. I use them on all of my headphones (except my PFEs) because they are so comfortable and they don't slip very much at all even with activity/sweat.