Yeah, but think of it this way.

Hypno-disc-Body to get hold of, vaguely reliable, fast spinner.

Mauler-No body, faster (if not deadlier) spinner, but not reliable (it trashed Killerhurtz once, tore its axe and plough off, then ran over the kill-saws and broke down!)

Typhoon-very fast disc, no body, reliable. Plus, Typhoons teeth are lower to the ground than Hypno-discs, or Maulers.