I know that on my 190e, the car will first hesitate when I start it up -- have to go pretty gently until it shifts into 2nd gear. There are several posts regarding this on the web site. The catalytic converter needs time to warm up, and once fully operational, it should shift without problems.
If you have the hesitation once the engine is warmed up, you may have a problem, but if it's just hesitating when you first start out -- not to worry.
Hope this helps.
Running as fast as I can to stay behind!!