After I cut out the limb profile on the bandsaw, maybe grind it some on the drum sander(adapted drill press), I like to use the smoother side of an older, partially worn out farrier's rasp, held almost parallel to the limb, to level the edges of the limbs(I never use good, newer, sharp tools on glass).
Used properly, the farrier's rasp levels and smooths at the same time and the resulting 'shine' makes it obvious where more work is needed to establish a perfectly flat edge with no low spots.
Sometimes I switch back and forth from that to a 10, 12, or 14" double cut bastard file... it all depends. It's hard for me to say because I switch tools by feel/instinct, I've amassed a good collection, and all are within arm's reach. I use so many files and rasps, I don't like to choose just one for any certain purpose, or even advocate just one or two. I think we should each have an extensive selection/collection and use whatever feels appropriate at any given moment... upon whims... like an artist in a flurry of paint, palate, and brushes, and tomorrow the same situation or idea may see a whole different arsenal employed.