I have one in my RR. 354 gears and G60x15 tires, 2,500 gives me around 75. If you plan on driving your car any on the Inter State then I'd do it, around town, maybe not. You're not going to any racing with just a three speed, and it's not a slick shift, ie speed shift racing. I have a 528, so I can just torque around town in 3rd gear with no problems. Bottom line, make the choice according to your intended usage.