Hey everyone, first time posting here, but I stumbled across this forum while trying to figure out some issues with my new 2021 Corsair Reserve 2.0 in Flight Blue. I'm the previous owner of a 2018 MKC 2.3 Reserve in Rhapsody Blue that I loved very much, but it was coming up on it's lease and I was given a great deal vs. purchasing it off of lease.
My 2018 MKC was nearly perfect. Great acceleration, ride, comfy seats, and 0 problems. While the 2021 Corsair's ride is definitely more refined and even more quiet, with the new transmission using the 2.0 power almost as close to my old 2.3, there are a couple of issues. These are all things I read on here, so I know I'm not the only one.
Once in a while, I get a deep "thud" coming from the back when it's windy out and my windows are NOT open. Also, the car is almost un-drivable with a window open past 40mph if it's breezy. You have to open all of the windows or the thud becomes constant. My MKC would do something similar if you had the drivers side windows open, but it was tolerable and not considered severe. This is something I've never experience in any car I ever had. You'd think they would run these designs through a wind tunnel under varying conditions before putting them on the road.
Second is the 2.0 engine cover, which I received some answers on when doing research. I was cleaning leaves from my car 2 days after picking it up, and when I lifted the hood, there was just a mess of wires without the engine cover. I immediately called the dealer thinking it was missing, even they got nervous. They called me back and said, "we ran the 
VIN and it doesn't come with it". I didn't believe them at first, and then another dealer told me the same thing after running my 
VIN. I called Ford/Lincoln directly, and they got back to me, explaining it doesn't have it anymore but couldn't articulate why.
I know my MKC 2.3's cover wasn't solely for appearance, and had sound deadening material in it. It's weird because the Corsair 2.0 motor still had the grommets for the cover, so I knew it belonged. After searching hard, I found a 2.0 Nautilus cover and it lines up perfectly. Low and behold too, it is not just designed for looks, but has a sound deadening function as well.
We'll see if they have a recall on the wind/noise issue, but the engine cover issue is one you'll have to solve on your own.
Those are my 2 issues, and everything else I knew what I was getting into when I switched from the MKC to the Corsair. One thing I can say is this, even though I like the Corsair's ride, design, and stereo, it's a car that'll have to "grow" on me: whereas I loved my MKC from the start.
My thoughts are that if Lincoln doesn't fix some things soon overall, they're not going to survive as we know it. It'll go down in history as a car company that had an amazing comeback and couldn't hold onto it due to bad decision making/cutting corners.