I preface this by saying I dropped him last week in a private league. I'm in a bit of a different situation as my league only uses 1 starting goalie, so there were/are starting goalies available in FA. I was able to get Vokoun in FA.
If all that is available are strictly backups, I would hold onto him. If there are platoon goalies available (Roloson, Biron, Smith, Niitymaki, even Howard to an extent is platooning with Osgood) then it's worth considering. I still have Mason in the public league I'm in, just because there's really no one else available.