I wanted DSG at first but it was typically an extra £1000 I couldn't justify at the time, I was glad afterwards after hearing about a few of the problems, but then some have trouble free motoring and love the DSG. Swings and roundabouts.
My dad is in love with his multitronic or whatever they call it in his Audi A4.
And yes i've heard mechatronics are £1800 to do or something which is a vast amount of money
What sort of DSG issues are you hearing about?
My Passat DSG is on 125k and still going strong.
To clear up a few myths:
The mechatronic unit is the DSG's brain, it looks like a big PC board thingy and fits directly inside the gearbox (but is accessable though an inspection plate)
To replace a mechatronic unit will cost around £1200 - the most of that being the Mechatronic unit, at around £1000 (it can vary slightly depending what car it is fitted in and what year)
There are a 3 main reasons why they fail:
1 - there was a small batch of faulty ones, but we picked most up under warranty years ago
2 & 3 - the main reasons are people not changing the oil enough or not using the correct oil.
The DSG boxes require the oil and filter changing every 40,000 miles - this is very important as the mechatronic unit bathes in the oil, and if it gets oil/the wrong oil is put in, then it can cause a lot of damage.
The amount of people who just put in normal ATF is shocking, and it will damage it.
If it was me, id be changing the oil and filter every 20,00 miles, as it will make sure it's kept in tip top - think of it in the same way our engines can go 12,000 miles between oil changes, but changing the oil at 6000 (like a lot do) will keep it that little bit healthier.
If treated well (correct oil and at least at the recommended 40k changes) then there is no reason why high mileages will cause issues - I drove a mk5 gti a few months ago on 135,000 miles and the DSG felt lovely and tight with no issues, where as the PAssat I drove last week was borderline undriveable.
A good way of testing a DSG box is when you pull off, don't pull off quick or normally, instead pull off very slow - so with the foot on the brake, put box into D, left off the brake and gently touch the throttle -a perfect DSG will pull off lovely, a good DSG will have a split second then pull off, but a bad DSG will not move for 1/2 - 1 second, then snatch harshly and tend to kangaroo - unless you pull off very slowly you may not notice this as you will be expecting it to pull off quickly. (If a box is doing this then it will be the Mechatronic at fault, rather than the box itself)
A failing/damaged Mechatronic unit will usually give the following symptoms:
Slow to take up drive
snatching gears
not selecting certain gears
As per any other gearbox type, they can break or fail, but it's not common - I have replaced 1 box for an internal failure in the past 8 years.
Mechatronics can fail, but again not common, 99% of failures are down to neglect.
If the DSG box were to fail (Not just the mechatronic unit) then it is expensive - some DSG's can be £3500 +, but as said the actuall failure of the boxes is very rare - I mean for every one person that posts an issue on a forum, there will be 200,000 who are still fine
They are a good box, if I had to have an auto box then it would be a DSG (or Audi equivilent) and they suit trubocharged cars very well due to the change is so quick you don't have much turbo lag - they also suit the R32.
With diesels, I tihnk they suit the engine, but one big downfall is the boxes want to shift into 2nd very early, which if you are crossing around about it can leave you off boost, but knowing that will happen means you can 'drive around' that issue.
Hope that might help a little.