At the halfway point of the season, when you have the choice of swapping cars, I will substitute the BMW M3 E30 DTM for the Group A, since it's a more competitive car.
Current car ranking (RSR):
1.334 Alfa Romeo 155 TI V6
1.341 Mercedes-Benz 190E EVO II
1.351 BMW M3 E30 DTM
1.364 Ferrari 458 Italia
1.387 Ferrari F40
1.406 KTM X-Bow R
Depending on how the ranking evolves until the car swap, I may substitute another car for the X-Bow too, unless someone desperately wants to stay with that car.