What do you think of jumping from 265 to 275 for rear tires on a Cayman? I have 265/40ZR-18 Michelin Super Sports currently mounted on the rear of my Cayman. I want to match the new (3 month old Michelin Pilot Sport A/S 3) fronts put on by the Benz dealer where I bought my car (it was a trade in) before I purchased it late August. They (A/S 3) aren't available in 265 and I want to replace the existing rear Super Sports with these before Spring. For now the Super Sports are okay with a few thousand miles left on them. I don't track the car. Had I purchased the tires myself I would have made sure to get the Super Sports all around but unfortunately the front A/S 3's were already there.