The low part might also be a reason for your intervention but for now will continue on to assume it is the change in steering rack as this seems most likely with the info provided.
The 1m unit has many differences and I am well aware there will be newnissues that come with it, but most will be once in intervention not when it does. And hence it was a suggestion as just an alternative because it will likely fix your specific problem, and the new issues might not be a problem for you.
The 1m/M3 unit has a different motor for the pump. I believe the control units are the same. M3 and believe also 1M use DSC8 where as ag 6cyl uses DS8+.
The vehicle dynamics models for the 1m will obviously be completely different but in away that's close enough to a higher performance version of what of your car was standard, where as now the standard 135i models in your unit are lower performance than what state the car is now. Same for the brakes. Most of the differences would mean you would likely only notice that they only really effect how it intervenes rather than when.
