Just swapped to 18" Michelin cross climate 2. I'm surprised how much more comfortable the 20" Perelli tires are. Although I'm seeing a 10-15% increase in efficiency, so I'm not complaining. :
Michelin CrossClimate 2 Tire provides great grip, braking
Single - 225/55R18 Michelin Cross Climate 2, Used Tire – Green Tire Store