yah.. its an unending dilema.. bin vs offer... afternic and other reps will tell you they have far more sales done through bin.. and will always recomend u set bins.. I am sure you heard it before.. and I don't mean just afternic and their premium network exposure with bin.. I mean all markets.. sedo.. gd... they always tell u this..
the probems with bin is that for larger folios, it consumes a lot of time to set bins.. unless you have all similr quality names and you set same bin for 80-90% names.. then like other said, u have to keep track of what sold etc.. else u sell, don't own domain, and likely get banned etc..
plus on top of it.. you may sometimes run into buyers willing to pay more than whatever bin u may have thought is proper for your name.. which is where makeoffer and negotiations would come in handy...
all in all.. its inconslusive.. and will remain so forever imo
imo