[m110]

Firstly, don't use the Universal model shown, just get the one for Porsches (and other German cars)
From my college inorganic chemistry class: if you rinse a clean motive bleeder with fresh fluid twice the residual old fluid is essentially nil.
If one wants to just bleed, the Motive can be used empty as a pressure source with no mess at all.
It will inject air if you go through the entire volume and don't pay attention. Pay attention.
Nothing wrong with the Mityvac...numerous factory shop manuals now show changing the oil on the ground, no hoist, no drain plug. Not my preference.