Very true and on this I agree.once a dear friend of mine who is also passionate about music reproduction accompanied me to Berlin during a concert at "La Philharmonie", leaving the hall he said to me: this hall is a little low on bass and the eardrums are a little dry...... For me the sound I had just listened to (Mahler the titan) was wonderful "De gustibus non disputandum est" (and his system is for me one of the best heard in my city)... In F 1 the car that wins is always the one that it was born with the best balance between engine and aerodynamics, then the set-up and aerodynamic load varies based on the track but no matter how hard the others try, it always wins. Even a hi-fi system, if assembled well from the start, is the one that is most capable of highlighting the characteristics of an out of the ordinary device. I don't know your system and your listening room and if it's okay for you to load the MSL at 50 ohm, far be it from me to dispute your statement, my clarification is based only on what is prescribed in the MSL installation manual.
Many cartridges I have tried in my system was supposed to be loaded with both 2-3-400 ohms, but it always sounded bright, sharp, edge’y, and lack of bass with that high impedance.
Having an all designed Dan D’Agostino amplification here, I have found that even the most analytical cartridges works best with a lot lower impedance here than in other systems. I have got this verified first hand by the swedish Lyra cartridge dealer, that could not believe his Lyra Atlas could sound so good, in the way it did here with that low impedance. So it is quite remarkable.
Same goes for Ortofon, Soundsmith, Koetsu, MSL, Shure, Nagaoka, AirTight, Miyajima, to name a few..
Hope you find the right loding for your MSL in your system and that it will sound great! Enjoy your music.
/ Jk