Pyrate/FFS' posts are always long, but usually good reads, unlike a lot of posters.
I am of the opinion that people who focus on methods of acquisition are overplaying it somewhat. What matters is how well a player is suited for the system that you are trying to run. If the Bills believe that all three guys fit their system, what difference does it make between free agency and the draft?
The other thing too is it also depends on how much patience you want to have building that position. The draft seemingly takes more time, given young players needing development and a limited number of picks, than already-ripened free agents do.