I'm not "so high" on Bernier, I'd just rather take a chance on a promising 24 year old goalie than take on Luongo's retirement contract.
I think about it like this: Luongo has probably 5 or 6 good years left in him. Will Toronto be in a position to win a cup in that window? I don't think so...particularly not if even Vancouver wants to be rid of him while already in a position to win a cap. We need our Schneider/Halak/Elliot/Price/Ward/Quick/Hiller.
So avoid the extra 4-5 years during which Luongo's contract would cripple the team afterward, try for a much younger, much cheaper goalie. If that works out, it's a goalie you'll still have around when the team is finally a contender.