I saw Greg Mills, standing in for Hugh Panaro. Mills was top-notch, and could easily play the Phantom full-time. The only spot in which he seemed a bit unsure was in the graveyard scene -- standing on top of the hedge (or whatever it's supposed to be), he balanced himself by putting his hand out and touching a grave. I can't say I blame him for being slightly off-balance in that scene -- only a cat or a mountain goat could be completely sure of standing without steadying oneself in that scene.
Frankly, I liked his interpretation better than Hugh Panaro's.
Audrey, the Phantom Phanatic, who nonetheless would rather be Jean Valjean, who knew how to make lemonade out of lemons.