Did mine a couple of weeks ago and it's still going ok.
The gauze had stopped a bit of carbon over 100k miles so to be on the safe side I've upgraded the ridiculously small oil filter to something better.
I wonder if the carbon build up is quality control issue. Injector #2 was very coked up and the nuts were finger tight. 1 and 3 were not very tight, 4 was very tight for a 6mm stud.
Replaced all the copper washers and ignored the WSM tightening the injectors well over the book value but still 60% of UTS for a 6mm 8.8.
Oil flush cleaned it out well but i'll put a fresh filter on after 500 miles just in case; hopefully good for another 50k miles!
Thought the sump might need a reseal but it's oil tight for now.
Should add I was quoted £500 plus for the injector job but it is dead simple.