On the field, Williams has displayed the potential as a No. 1 receiver.
A fourth-round draft pick in 2010, Williams led NFL rookies with 65 catches for 964 yards and 11 touchdowns. Though a hamstring injury limited Williams to just six games last year, he has 215 catches for 2,947 yards and 25 touchdowns in 54 career games.
The Bills are in need of an experienced player to complement returning starter Stevie Johnson, who led an otherwise young group of receivers.
It's off the field where questions have arisen.
The Tampa Bay Times has reported that Williams' neighbors in Tampa were unhappy with noise issues and damage to the player's rented home.
Without providing specifics, Williams said two of the numerous accusations were made up. When pressed on which two, Williams said the Bills requested that he not discuss it.
In trading Williams, Buccaneers general manager Jason Licht referred to the deal as something the team "felt was best for both sides."
In Buffalo, coach Doug Marrone is willing to provide Williams the benefit of the doubt. Marrone was in his first season at Syracuse when Williams left the team.
Marrone signed off on the trade by saying what happened at Syracuse "is in the past for both of us." Marrone went further by picking up Williams at the airport upon the player's arrival in Buffalo.
Williams said he and Marrone cleared the air by speaking on the phone before the trade was completed.
"He made mistakes. I made mistakes," Williams said. "The situation wasn't handled how it was supposed to be handled. But the past is the past. So we're kind of looking forward."
Williams acknowledged that one of Marrone's concerns at Syracuse was the player skipping classes.
That won't be an issue now.
"He didn't think I went to class. But since it's the pros, he knows I'm going to go out there and do my job on the field," Williams said. "You're always going to get the great Mike on the field."