I am a midlands guy so I can't speak about others around the state, but I would have to say Blythewood is looking pretty good. It doesn't seem to me that they have the State Champion aura about them, but they are very sound.
Then, of course, you have to throw Lexington, South Aiken, Sumter, West Florence, Conway and those guys in the conversation in 4A.
In 3A, you can never count out AC Flora and Chapin who are both having very good years.