They showed how they cut off the legs on Reaper Live, basically heat em up (boiling water) and they cut really easy with an exacto.
I don't think they are a good candidate for magnetizing though. That was originally my plan but they appear to be very hollow, which means you would have to create the seat for the magnets yourself and get everything flush on both sides, which would be difficult.
I have an idea how it might work, though. Maybe cut the legs, fill with GS/other sculpting medium, push magnet in place, left that whole side dry. After that side cures you attach the magnet, fill the other side with medium and push the hardened side into the uncured side to force the uncured side to conform to the cured, then detach and let dry. That should also make an impression for the second magnet. Think I'll post this in the current hut discussion to kick the tires on the idea.