I'm with Ryan (Trollog) on this one,
I tried the old spade bit when I started my apprenticeship, they last a few days, at the best.
Get yourself a good auger bit, they are available in diameters from 5/8" up to 2".
One other thing, the easiest way to break your wrist is to use a spade bit in hard Red Pine, when the drill jams.
