I found a dremel bit that is a cotton/cloth wheel that is 3 time as thick as the blade and just fits the hole of my Dragonfly (that was quite sharp). I placed a little bit of polishing compound on the wheel and attached it to my drill. Make sure to have a good grip on the handle of the blade and the drill on a low clutch setting as to not allow it to spin out of control. I ran it on there for a while moving it a little side to side and twisting a little to get the edges and it turned out perfect. I ended up with a nice and smooth Spydie hole and a little bling with it being polished to a nice smooth finish. My other knives (and most recently the Para3) didn't come as sharp but I have been thinking of doing the same to get the inside of the hole polished and shined up. I just haven't found the right size buffing wheel yet, as the PM2 and Para3 are larger. I figured that using a wheel of similar size to the Spydie hole will help keep from making the round hole oblong.
Dragonfly G-10, Blurple PM2, Para3, Jani-Song, Dragonfly2 ZDP-189, Lil' Native, Chaparral LW, Delica WC HAP40, Para3 M4, UKPK red G10, Para3 LW, Para3 LW M390