Like I said, if you used the sunroof and rear window, no risk. I need to test putting my rear wheel holder closer to the back edge or even on the wing, it does deflect a good bit when in the middle of the roof panel with my mountain bike. Like you, my road bike is sub UCI weight limit and barely has an impact when mounted.
Depending on how much you're transporting it, those trunk mount saris racks I used to have good luck with. I personally placed felt tape on the feet and angled the bottom so I could still open the trunk. They were my favorite in sedan owning days. Hitch rack on the suv I've slammed my shins, hip, and shoulder many times. Roof rack is basically pointless now and support for them seems to have almost disappeared in favor of hitch racks. I think that's mostly because of the industry dropping quick releases and people being too short and weak to lift bikes overhead on taller vehicles (which they're all tall now).
Depending on how much you're transporting it, those trunk mount saris racks I used to have good luck with. I personally placed felt tape on the feet and angled the bottom so I could still open the trunk. They were my favorite in sedan owning days. Hitch rack on the suv I've slammed my shins, hip, and shoulder many times. Roof rack is basically pointless now and support for them seems to have almost disappeared in favor of hitch racks. I think that's mostly because of the industry dropping quick releases and people being too short and weak to lift bikes overhead on taller vehicles (which they're all tall now).
I'm in the middle of carrier shopping myself... Sadly looks like a low hitch rack is the only option that fits my wife's and my bike, but I'm not excited about the reduced ground clearance and something hanging an extra 5ft off the back
Throw the road bike inside. So much easier. Only time that doesn’t work is if you have to leave it in the car for a while. Then it’s just an invitation to receive a broken window.
Then for the sake of simplicity and cost, I'd personally take a look at the saris bones trunk rack. Saris rep years ago told me to rotate the bottom feet to face the trunk and use the bumper as a ledge and not a base. Worked for me for years and I could access the trunk.
I haven't had those issues personally. I'm sure it depends a lot on the car shape, and how it's setup, bike size, etc. With those kinds of racks, or even hitch mount hang style ones it's hard to get away from some tire sway from the front. That's usually where I've found mtb to be most annoying.
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I bought my Canyon from a buddy that upgraded to a new Domane. My riding partner has an Aethos.
Don't forget, you have to say Turbo every time or PPNT will get you.
