All of these machines are worlds safer than swinging an axe which can hit your leg or foot and leave you injured. Like any machine, you always keep fingers and hands away from the moving parts. Bad video title
Great stuff! Imagine landing here because you searched for videos of big impressive choppers in action... !
The only truly dangerous ones were that ones that came over and through the slit on the table or wall, every other was safe with respect to the tool!
Safety is in the proper usage of any tool. I think these are all great. I do think the human powered inertia splitter could be improved with a counterweight in place of a spring though.
Overall value for money and simplicity and safety .. I vote the spiral cone the best ... it could do with being 200mm longer to assure it splits all the way through.