As far as southern rock goes...

NeedToBreathe >>>>>>>>>>>> Kings of Leon

In my opinion.

(And yes, maybe instead of listening to a bunch of old music, I just went through iTunes and bought a bunch more NeedToBreathe stuff I didn't own.)

But seriously. Listen to Washed By The Water, These Hard Times, Don't Wait for Daylight, and More Than. Just do it. They're brilliant.