The stove I linked to in the first post isn't exactly a rocket stove, it's just that the intake air is directed from the top surface, through the throttle plate, then down to the bottom of the stove via a square tube. I think this is mainly to keep it fully eclosed and spark free for workshop applications. There's no hearth as a consequence, just the bottom of the box, so it's recommended to keep a layer of ash in the bottom to protect the metal.
I only tried sawdust once, it worked okay but there was too much pongy fumes outside for my liking so now I just burn logs and you can't even see any smoke.