Pretty good. Lots of options to play with, and the animations / physics look good, no weird ragdoll physics or unnatural snapping into positions.

Suggestions for improvements:

1) A common issue with games that allow the user to rotate a camera around a subject in 3d space is that angles can get awkward and it is non-intuitive sometimes how to get things re-aligned. You certainly can do it, but having a button to reset the camera back to a known starting state would be a nice quality-of-life feature.

2) The tentacle you get from "Tentacle Skin (Front)" doesn't render / is invisible. The other locations don't have this problem.