Be very wary of the 7 speed DSG! They have a major flaw with the dry clutch pack that overheats and causes judder. I've just traded mine in as it got so bad the car was a nightmare to drive. Works perfect for the first hour or so but after that the judder can get quite violent (especially after a lot of up and down shifts on A and B roads but is fine on motorway). Do a search on DSG 7 speed clutch judder on google and you'll see what I mean - there are hundreds of posts on the subject. This is a known
problem by VAG and replacing the clutch pack only fixes the
problem for a short while and it comes back. There is 'apparently' a fix and a modified clutch pack but a search on google reveals that it doesn't work long term. There was an advisory sent out by VW saying they are awaiting a fix but as of yet there isn't one that is permanent. Incidentally my car had only 40k on it!
The DSG fluid change was part of a recall in China due to mechatrnics shorting out caused by humidity and use of synthetic oil (although this
problem happens in other parts of the world as well and the fix is to change the oil to mineral oil). The gearbox oil and mechatronic oil is separate on the DSG 7 which is different to the wet clutch 6 speed DSG that shares the oil in the mechatronics unit, clutch and gearbox hence it needs replacing so often. So replacing just the oil on in the gearbox on the 7 speed DSG won't do anything and to do the mechatronic oil change is highly specialist!
As far as I have read VAG are working on a new actuator to prevent judder/poor clutch engagement on the newer cars but I have no idea if this has been implemented yet.