Okay, some mixed comments above, some I can agree with, others not.
Wider tires will offer more grip.
Wider tires will reduce economy.
The car is heavy, so wider tires should be expected and required to improve cornering ability/limits.
The particular issue I raised though is acceleration.
These cars generate huge torque at low speed and it is this that will most likely break traction.
I dont see 245s handling this (nor 265s for that matter), which means acceleration is going to be traction/electronically limited which blunts one of the big selling points of the car.
Not being an owner (yet) - does the instrument cluster flash a traction control/stability warning light when the wheels slip under hard acceleration?
Does this happen on dry roads in good condition?
And is there any evidence that 245s slip more easily than 265s on launch acceleration?