30s and 40s are fine if people are actually doing the limit, and that means actually doing it and not dithering around 25mph or 35mph. Its even worse when most 40 roads around here used to be NSL roads and doing 35mph along them is just so tedious.
But....by far the most irritating driver is the one who does 30-40mph...everywhere. I was in a 15 car train behind one this morning and you could tell everyone was getting a bit wound up, people were having to brake every now because they were getting too close to the car in front and you could see people were looking for overtakes etc. Anyway, the car finally pulled off and everyone who was behind briskly went up to 60mph and as if by magic the proper 2 second gaps between cars started appearing with no one tailgating, no one becoming impatient and the road just flowed brilliantly. Its amazing how one selfish driver can, rightly or wrongly, cause such a hazard to everyone else. I prefer to get passed these people swiftly as they are also often the ones who'll make erractic maneuvers, come to dead stops at clear roundabouts and all sorts of other strange driving which is just tiring when you have to constantly be on full alert for it.