I would say drive personally. It's only 150 miles and unless you drive very slow (which you wouldn't be because you can drive very fast on 20), it shouldn't take much more than 2 hours to complete this trip at the very most. Unless you value 500 miles and wasting 200 bucks just to wait in ATL for the connection provided there are no delays, and fly the 20 minutes flight, then go for it.