Atlanta rush hour can be hit or miss. My last time through was a Monday afternoon in early October, approaching from the west on I-20 East, headed to Braselton northeast off of I-85. I chose to head into downtown to avoid the I-285 perimeter in Cobb County. It was sucky, but not terrible, based on my NYC metro-based frame of reference. From the I-20 and I-75/I-85 interchange, it took us about 1:30 total. Could have been much, much worse.
My son routinely has to drive through as he goes to school at Auburn, and it is the only real way to head home, as well as driving instructor jobs he has at Road Atlanta in Braselton and Atlanta Motorsports Park in Dawsonville. Those trips should take 2 hours for the first and maybe 2:30 for the latter. He's had a few that have been over 4.....