I prefer pricking irons myself. Since I usually work in heavier leathers, I give 'em a good whack, then finish the hole with a sharp, stropped, polished diamond stitching awl.
I don't often use a groover but when I do it's on 9 ounce otherwise I'll crease the stitch line or just mark it with dividers and off I go.
Edges, I'll sand, bevel, wet the edges with water, burnish and let dry, then gum trag. and burnish and let dry, sometimes gum trag. again, burnish again and let dry. Finally a coat or two of Tan Kote and burnish again.