I think it'd be a fun series. It's the best offense (FLA) against the best defense (BOS). I'd have to go back and see how similar situations have played out in the past, but my suspiscion is the defense would win out. Both teams have goalie question marks. Bob has more experience but is the sample size of him being meh to bad is quite long now. Ullmark is probably playing the best of all 4 goalies, but has zero playoff experience.
FWIW, these regular season juggernauts have a weird track record of flaming out. Not sure there's a rhyme or reason, but there have been 4 120 point teams since 2000. 3 were bounced in the first round, the fourth lost in the 2nd round.
05/06 Red Wings...Lost to Edmonton in the first round
9/10 Capitals...Lost to Montreal in the first round
15/16 Capitals...Beat Philly in the first round, lost in the 2nd round to Pittsburgh
18/19 Lightning...Swept by CBJ