Is Cliff Lee Really That Good?

The bidding war/stalemate over Cliff Lee raises a good question.  Is he really that good?  Is he another Barry Zito waiting to happen?  Last year he was only 12-9, with a 3.18 ERA, and 4-6 with a 3.98 ERA during the second half in a Rangers uniform.  He got spanked in the World Series.  Overall, I'm glad other teams are going after him.