It’s still in warranty but I would just put the standard pipes back on if I had to go back for an issue.
I’ve got a Golf that is Stage 1 tuned still in warranty that is supposed to flag a TD1 if the dealer scans the ECU which would void any drivetrain warranty, a risk I was prepared to take.
Wonder if the M3W ECU records adaptations it makes for free flowing exhausts, I doubt it.

This is the Golfs 0-60 using Dragy ,a gps device, will do one in the Morgan when the weathers better.
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