Updated on my Wife's car:
1.) After the car went in for a regular service with the agents (so that I could get the FSH stamp) they recommended replacing the rear disks and pads. Was quoted R2390 for parts and R550 for labour. But since this is a relatively easy DIY told them to leave as is. They reported the blocked PCV on collecting the car and it then developed a massive missfire - bought the required parts and had a flat-bed collect the car and take to a specialist in my area to fit the new parts. All was fine although the power was down and for almost two weeks could not understand what was going on - turned out that they had not reconnected the Vanos, so while I was removing engine covers I noticed the loose connector, plugged in and problem solved!
2.) Okay, back to the brakes. Wanted to stick with ATE disks and pads and eventually got a very good price from Midas. Paid R2670 for front and rear disks, pads and brake wear sensors! Agents wanted almost R3000 just to do the rear brakes! And they also use ATE as far as I know...
All done, now just a bit of a clean up. Had to used loads of "gentle persuasion" with the hammer and penetrating lubricant to get the first disk off - the rest were the same process.
So, all four disks replaced and new pads all around, new brake wear sensors, copper slip on the backs of the pads and wherever some lubricating is needed, bolts etc.
Took the car for a drive to get the disks and pads to gently agree with each other, then went to my personal testing stretch and gave it a few up to 100 km/h and then hard braking until I smelt hot brakes, then gave them a cool off without allowing the car to be stationary, so no chances of heat soak.
Can already see that the cross-hash on the disks are practically gone, although there is still the rougher sounding noise when braking, so I reckon a few days and it will settle.
Will take some pic, more specifically of the old disks and pads - the rear disks were very worn, but the front pads were particularly worn and the disks too, so made sense to do all four in one go!