I know this is an old thread but I am throwing my 2 cents in for future readers. The OEM Michelin MXM4 94v SL 245/40/r19 has been surprisingly poor performing, for me. It is a smooth quiet tire. Those are the only two good things I can say about it. At proper inflation, these tires could no longer handle wet roads after 15k miles. I couldn't even get the car out of my cove to go to work during a very minor Memphis snow event. And they lasted no more than 25k miles before the tread was useless and my shop was unwilling to even rotate them. For a tire that proclaims to be in the sweet spot of an all-season, good handling, comfortable ride, and tread wear, I've had and now have better for less money. Never was a fan of Continental but the the Extreme/Control Contact rated better overall in dicey weather than all others except the fairly new Vredestein Quatrac Pro, and I'm willing to endure a little extra road noise for the extra grip in the rain. I usually keep my music too loud to hear it anyway. As a bonus they were $20/tire cheaper than MXM4. Your priorities may differ.
But after extensive research on the internet when tire shopping for the mkz, it seems rarely is anyone getting 40k miles on any brand in this tire size... touring a/s, performance or otherwise.