285 is a parking lot very often and worse IMO. I always do I-75 to I-20 going that way. Don't hit it at rush hours though, its very bad many of time, like a 30 mph crawl for an hour or more and then full stop while a wreck is cleared. I go through there around 1pm to 3pm fairly quick, its always busy though. I worked down town for years.
I was on I-20 at 6pm a couple months ago and it was like bumper cars, parts flying everywhere. The traffic there is nuts and the drivers are very reckless. Big commercial trucks tail gating bad, lots of collisions. Saw four major wrecks in 30 miles going west bound from Augusta. One wreck involved about 6 semis and a dozen or more cars. I had to weave in and out of three lanes missing debris with my 5th wheel.
So, avoid the ATL at peak times. Better off to park it and wait IMO unless you can hit it at off peak times. They fly on I-75, its very interesting after 5pm on a week day. I was running 65 mph with the RV and they pass you like your not moving! I travel from Chattanooga down though Atlanta occasionally with the 5th wheel, I hate that area after 3pm.