Every manufacturer has hiccups, I agree that Mercedes should rise above and have less quality problems as well as being the best at solving any problems and satisfying their customers.
However, I think that this quality problem is also a dealer problem. I swore off new Mercedes cars several years ago when I became extremely frustrated with my local dealer. I have since moved, and decided to buy a new Mercedes again.
My experience so far is that I have a slight 1-2 and 2-3 shift flare, which needs attention. One dealer has told me that it is normal, and that any changes will make the car drive worse, a different dealer has told me that it needs to be fixed and that they will reset the transmission adapts and see if that fixes it. Same problem. The car has been otherwise flawless for its first 10,000miles.
If your dealer does not fix the problem, move to a different dealer AND LET MBUSA KNOW ABOUT THE SERVICE AT EACH DEALER!!! Mercedes and the Dealer Manager can not fix the dealer problem unless they know it exists.