How long does it take to drive from Swellendam to Plett Bay?

about 3 hours

Hmmm, I would say 3.5 hours, 4 if traffic is heavy.

Well, map24 reckons its 303km and will take 3:04 hrs.

I checked the Shell Geostar site yesterday, but didn't post. But from what I remember the distance was 303 km, as #3 says. And my own expectations for a "N" 120 km speed limit highway would be an average of at least 100 km/hour, if there are no major roadworks or unusual traffic. So that would be 3 hours at most, as #1 says. Yet I think that site said 4 hours. Perhaps erring on the safe side.

Thank you all very much! Especially for the map resource :-)

Arthur, nope. The problem with that stretch is lots of stop and go roadworks + lots of 80km/h zones between Wilderness and Plet.

Yeah, I did remember that that section was probably the one that I keep hearing about in the morning on the radio traffic reports. With Rob Byrne always adding "so give yourself extra time". I never said so, because I wasn't certain. But I did cover myself by saying "if there are no major roadworks". ;-)