I'd honestly be more impressed if that cylinder-cube worked like a proper 3x3x4 cube. It seems to me this is just an extended 3x3x3 with rounded edges. Im not saying this is trivial to make. But not very interesting from a puzzle-solving perspective.
My favorite puzzles are the ones like gigaminx, olympicube 6/7 and superoctahedron (not sure i recall name properly, but a higher order octahedron anyway) ...