I have not driven a brand new cl9 so i do not have an idea how it's shift should feel like from 1-2.
When i bought the car 1-2 shift was always noticeable, there was a delay but it would shift with a smooth jerk. After 2 months driving, the second gear jerk started. I first noticed it when driving to murree. It used to shift normally and sometimes give a jerk. I made many errors trying to fix it. The biggest error was to clean the transmission filter using compressed air and reinstall it. That gunk did not fully remove from the filter and was reintroduced to the transmission. Another error was to change ATF to nonoem. Both these things caused the transmission not to shift at all. Car only drove in first 2 gears.
Eventually, the transmission code came up and i had to replace 3rd pressure switch and the shift solenoid. Also did 2 drain and fills with dw1. After that the transmission started working for all gears. However, 1-2 shift was no longer smooth. It always jerked. The way to avoid the jerk was to lift of the throttle when its shifting from 1-2.
A week ago again my transmission threw an error and it was not shifting into 3rd gear.
I got the shift solenoids serviced. 2 tubes in the front shift solenoid were choked.
Got them cleaned and did a transmission oil change. And now the transmission is shifting fine so much so that the 1-2 gear shift has also improved although still not perfect but i am satisfied as I have driven this car with very bad jerks.