This is not the point of the thread.The Hankooks on my 2009 Malibu (company) car are noticeably better than the Firerocks that were on a rental Malibu I had for a time. However, if the car were mine and I wanted a really nice tire, I wouldn't hesitate to put the Michelin Pilot Sport A/S on it. I have them on my other car and simply love the smooth quiet ride with amazing traction and long life. I have 60,000 miles on a set right now, and they're just beginning to show signs of not being as sticky as new. Of course, the car itself also has 60,000 more miles on it so that is a factor in the decreased ride quality too.
That GM substituted a poorer quality tire, passenger tire for what the window sticker clearly states should have been a touring tire.
My OE size is 215-55R17 with a 93S rating. Tires available in that size are rare even allowing for a higher speed rating such as H. I have moved from S or T to H without negative impact or even went up a little on weight rating.
To expand tire availability, even the one you mention, I'd have to move to 225-50R17.