I am planning to change my Pirelli Pzero System (235/45/R17) to a similar series with a 245/45/R17 (or maybe 255/45/R17). The guy at the tire shop has no idea if that will be a problem driving on highway. I want to know if any one of you guys have tried similar tire on their S-line? Any problems?? I mostly drive on highways, so want to be sure it won't affect the safety and control.

Any thoughts?