Well I paid $150 for the change it was done using a computer. The tech road tested the car and told me that when this happens the car hesitates and seems to be searching for the gear. He says that it seems to be electrical not mechanical and he thinks a Mass Airflow Sensor might fix it. He doesn't speak good English so I have a hard time understanding him. Here is what I observed. It does upshift and downshift fine. The only time this happens is if I fully depress the accelerator like when passing someone on the highway or trying to move out of the way fast. It seems to shift better when I ease off of the accelerator after noticing the hesitation. It happens each time I floor it on the highway but never at low speeds. I understand how when you respond faster it shifts rougher but I am sure that is not the case here. I have driven a c280 and doesn't do this. This car has been in for all of its scheduled service appointments on time and has been very well taken care of.