I like watchign them "lurch" around as well. I like how they kind of turn their head sideways when they are dozing, lol. One of us should really post a video, its hard to describe how neat they are.
So, the conical snails that pull themselves along are rabbit snails? I was looking at a LFS yesterday hoping to get a scoop of MTS to help aerate my sand and I saw snails, but they weren't burrowing like MTS.
These are much much larger than MTS, they are 3" or larger but thye have a similar shape. The rabbit snails come in a wide range of shell and face colors as well.