How about the Laguna flashbacks?

They cause your party to faint/suddenly fall asleep, which I suppose isn't great for your health. All the dreams serve no direct benefit to Squall and co. except the dream Zell has (not seen by the player) of Ward working in the D-District Prison (the one window). This information helps the SeeDs escape the prison, effectively "saving" them from their predicament.

I don't know if that noise that precedes each dream can be called 'pleasant'. So I'm not confident about this answer.

Then again, I was pretty confident about the last. So you never know. xD