How bad is torque steer

As far as the Cooper S is concerned it all depends on the condition of the front tyres and whether or not the car is equipped with a limited-slip differential. I drove one with half worn front tyres and no lsd and under hard acceleration torque steer was very obvious (with the DSC off at least). Mine has a limited-slip diff and fresh tyres and it's completely different. There is some torque-steer present, usually when accelerating from standstill with Sport engaged and the DSC off or when accelerating out of a 2nd gear corner but not to the point where it becomes unpredictable and annoying.

I have just purchased a 2009 clubman s. I am looking to install the following: Magnaflow exhaust, Alta r-56 cold air intake, high flow throttle body 59.75mm, and Alta Access port ecu performance recalibration. So my initial concern was the torque steer. So if after installing the aforementioned and torque steer is bad, how would you minimize it?

Typically Cooper S (Clubman included) do not have 300 hp. Typically Clubman S are all turbo charged. And typically you have to use both hands on the wheel when under full throttle during standing start or abrupt kick-down (down shift), that is, even with electronic traction control on.