Rather than coming through Atlanta at the height of the rush hour, I'd either leave later as J suggests, or stop for early dinner at the McDonough/Ga Hwy 20 exit 215 and continue on after 6PM. Most heavy traffic that time of day will be on I-75 north of the city. Traffic on I-75 south of the city will be heading south, against you. The Varsity is unique and, IMO, not as bad as J lets on, but I wouldn't fight rush hour traffic just to eat there.
