Hi Roman and Co
Indeed thay are small and look cheap!
I am not too worried with the Seetal Crocodile or its sibbling the SBB Ee 3/3 switcher, which are relatively light and will never be heavily loaded anyway.
But I am truly concerned with the ICE 3, which seems to labour climbing with a full consist of 7 cars. That motor gets very hot after 5 minutes of running.
The buzzing is less of a worry as it is the result of the pulsed output on the decoder, which at low RPM causes a resonance in the motor. In fact in the case of the ICE3, it is strikingly prototypical!
Looks like Marklin is moving more and more away from their bullet proof historic motor design.
I can understand the cost reduction imperatives Märklin is faced with, but I treat the new motors with caution, and would think twice before having these new loks pull any of the prototypical length freight trains (80 axles +) that I love so much.
True also is that I did a "burn in test" with the first Re 485 SBB Cargo low cost loko when it came out in 2005 and I must say that it passed the test with flying colors. (I stopped after 168 hours continuous running at 75% throtle with 40 axles load. I just stopped the lok briefly once a day to check the lubrication).
Thus I am "subjectively" worried with the "cheap looking" motorization, although my isolated test seems to tell me that my worries are probably unfounded.
Time will tell.

PS.,oh by the way, I wish I were who you greeted me as above!