My last Cadillac was a 2007 DTS luxury with the magnetic suspension . My new 2017 CT6 has the magnetic ride as well but with very little rubber between the road and the pretty 20" wheels you feel the bumps like never before. I kept the 2007 for a few weeks and can't believe how much difference in the smoothness of the ride the 2007 has over the new 2017 and have to believe these low profile tires with large wheels must make up the difference. As for warranty, I am pretty upset that you do not cover these wheels since they come with the upgrade package. I have a strong feeling the first large chuckhole I encounter will damage the tire and wheel. NOT GOOD BUISNESS for such a great expensive vehicle. By the way, this is my 5th Caddy. I love everything else about it, but I always bought for the smooth ride and this may lose my confidence.
I currently drive a 2013 CTS and received a 2017 CT6 as a loaner car. Interior space is awful, I don't like the seat and I feel cramped inside. The roof is lower so my head is practically hitting the roof and I'm only 5'8. Overall, not impressed at all.