Austrian arguments often look logically airtight until you scratch the surface and notice how specious they are underneath. I can't even say that for this one, though. I don't even understand the justification Hoppe gives for jumping from rational discourse to the bits about homesteading and scarce resources. Perhaps this is omitted in the summary; it doesn't seem to be too informative.
As for Habermans, I always thought his ideas came from an overly idealistic rationalism, though I haven't read him in any depth. All my knowledge is second-hand from some historians I read who seem to love him.
The link you gave to the LvMI article outlines it. Notice the obligatory boilerplate "...and Liberty" in the title. Kinsella is such a clown; not many in the movement even like him. Also, check out the praxeological argument for intellectual property! What snake oil.