well.... i'm partial to the Milwalkee self-feed bits, they have a center spiral that is detatchable, and each bit is sold with two.
the fact that the center is removable lends to quicker shapening.
i use a right angle drill, makes for staighter overhead & knee level runs, yanks me around less than the hogs do.
i also have an older 10 hp 3/4" straight drill, which i'd probably bring to such a job if i really got my knickers in a knot, but it tends to wear me out quick, and sooner or later who takes who for a spin is usually in question