I mean - this question is kind of unfair. Ray Allen is a hall of fame player with an impressive body of work. He has been featured in several cities as the "star" player.
Courtney Lee is a fifth year player who has never been featured as the star of an offense.
That said - Lee, in 2012, was statistically speaking, a better player. He shot better from the floor, from three, and from the field, he had more steals and blocks (and he was a better defender). He's also younger.
But Lee isn't going to teach Jared Sullinger to shoot. And he isn't going to show Fab Melo what it means to be a professional.
A better question is whether I'd rather have Ray at $6M/season, for the next three seasons (until he is 41!!!) or have Lee, for the next four seasons until he is 31. I am as sentimental as the next guy but COME ON. It's a no brainer, Lee is a thousand times better as an option.
I wish Ray the best - except when we play the Heat. But way to go Danny!