Larry Lage of the Associated Press touches on booms and busts in recent years of free agency. His comments on Big Z.
"ZDENO CHARA: It's not easy to remember the huge defenceman playing for a team other than the Boston Bruins. They signed him as a free agent in 2006 after he spent his first eight seasons with the New York Islanders and Ottawa. Chara helped Boston hoist the Stanley Cup in 2011 and won the Norris Trophy in 2009."
Others noteables fitting each category in this link for his article.
http://www.metronews.ca/sports/2017/06/30/booms-busts-in-nhl-free-agency-during-salary-cap-era.html
What other Bruins signings in recent years have earned the Boom or Bust handle?
Whole heartedly agree on big Z being a huge boom and will tag Marty LaPoint as a big bust.