Had my F125 range switch and gearbox oil and filter replaced today

Mate didn't measure how much fluid came out as he left it to drain for an hour and got on with something else. He reckons a good litre then dropped out when the filter was unbolted and even with the minimal mileage mine has done the magnets had done their job catching any metal fragments working their way round the box. Said changing the F125 was a bitch - largely because there's next to no clearance on the exhaust downpipe, compared to the RS6 ones he's used to doing. I guess not surprising these switches fail if they're subject to serious heat cycling for year after year?
It took about 7 litres to refill the gearbox, so sounds like he got the vast majority to drain out. I'll probably get it done again in 2 years time and it should then be good as new.
There was nothing wrong with the way mine changed gear anyway - this is all preventative care, since the car's done only 42k to date. It's had a blast up the motorway since and I ran it into town earlier to get a slow puncture repaired and all seems fine with how the box is operating, including a brief bit of 'spirited' throttle use
Car was back at my house by 1.30 and had an oil change service as well - hopefully no more expense for a year.....
Although the ABS light that comes on some times when getting the car out of the garage has been traced to an intermittent offside front sensor fault. Doesn't seem to like jockeying back and forth before you get going - if you head off straight away it seems to work fine