@ Hersbird. My old 2003 TDI is still driving around with over 400,000 miles. I sold it at 240,000 miles. I had the intake cleaned at 200K miles when the timing belt was done but it didn't drive any different after. EGR is required to meet even 20 year old emission standards.
@Piotrsko: Why do you want a regen light? It doesn't matter if you interrupt a regen cycle, it will just restart the next time the car comes up to operating temperature. You don't have to idle it and let it finish. Turn it off and the car will run the fan until things are cooled down. Save fuel by not idling.
There actually is a warning light if the regen can't be interrupted and must be completed.
Before and after testing shows small losses in HP and Torque after the fix. This one is 2.3 Hp and 8.3 lb-ft of torque. They also show faster 0-60 runs AFTER the fix because the DSG holds gears longer.
https://www.cars.com/articles/we-tes...1420699480602/
The only drivibility "issue" I have is that my car has too much power at 2,000 RPM. It lags a bit off idle and then the turbo hits and the wheels spin if I'm not careful. I drive the 2015 at it was a bit smoother but the tiny annoyance wasn't worth $3,000 and I didn't want to deal with DEF.
Here is the thing. Driving a "fixed" TDI is totally voluntary. Original owners could sell back their cars at a huge premium. Owners like me know exactly what we were buying when we bought it. It isn't like this was forced on anyone.