My 21 P400 also revs high upon starting, almost to the point I'm afraid to put it in gear. it takes minutes for it to settle down. Bringing it up at 1st service + it has an active recall to fix.My tyres are set at 34psi i only ever run light load as only me in car so thats not it. better suspension travel on 21 “ tyres as well as a much better tyre prob say a michein pilot sport 4 like i had on an alpina would be far better. As for the sun roof when open & trying to close it it then would bounce back open several times. The dealership had to re align some bars on the inside of sun roof. Its fine now. My main issue is the wind noise from 70 mph coming from somwhere but dealer cant hear or find it so i will have to pay a specialist to find it. Also the lumpy running which dealer says is normal i am trying to reject car at present. I hate it wish i had never ordered it.
But on the positive, its MPG is fantastic....21 city and I've seen 28-30 hwy. And, this vehicle is super responsive on the throttle. Nothing like what you describe with the SVR.
It pours on the power immediately and seamlessly. So far we have had no fit and finish issues and overall are pretty happy...