2013 ATS 2.0T RWD, DP, Intake, HPT, CC
Pretty accurate, although the car's resale value fell so much they are attracting performance buyers looking more for a platform to build upon than a luxury car. Even still, handling rather than straight line performance seems to be the attraction.Here is the reality of Cadillac forums and Cadillac ownership: Except maybe V owners, majority of owners are not into modifying their cars. The most extreme common modification is tuning turbo engine, and that's all about it. I can be really wrong on this, but I doubt you can find more that very few owners around here who are willing to go through changing their rear differential.
This fact pretty much explains why aftermarket options for Cadillacs are very limited.
For the Quaife, if it can be done interchangeably with the Camaro, there might be enough interest, although I thought the Camaro already has some beefier versions. Might be easier to adapt the Camaro rear to the ATS; IIRC, there is a thread or two on here