exactly what i use it for- prototypes, one off jigs and such, spacers etc. its so useful for stuff that needs a certain awkward geometry and fairly high dimensional accuracy. i just dont see myself ever using it for production parts, though i do have a 6 ft auger i printed which has moved tons of material by now with no problems
i printed the flights a quarter at a time, and the have a 1" bore so the got glued to a wooden dowel, and i also printed little alignment pins on them for assembly
At less then $200, it is well worth it.