it is highly unlikely the bills get willis at 12 a lot of teams love him an know the bills want him so someone will most likely trade up to get him.
there are a few scenarios i see happenin, if peterson falls to 7 they trade up to get him, they work out a deal givin up their number one for lance briggs, or they trade down a few spots and draft leon hall in the first round and tony hunt in the 2nd