The 'tube-transistor' enigma by MC carts?

By accident I got to know an guy from Swizerland who has
worked for years as technician (R&D,testing,manuf.etc) by
Benz. I made some joke about 'Zelle',the expresion he used
to refer to carts,by asking if the carts are made by
prisoners? ('zelle' is 'the box' in the prison) He appreciated my joke and explaned to me in 2 sentences
something I never thought about. There are 2 kinds of
'bobins': iron and the other kind. The 'classical example'
of 'iron' is the Ortofon SPU. The advantage: stronger signal and some kind of 'pleasing warm sound.the disadvantage:(more)distortion.
The 'ruby-cross' bobin has (much?) less distortion but can
sound 'thin' depending on the rest of 'the chain'.
This is obviously the so-called 'Holistic' approach ;
aka Rauls 'it depends...'. Me? Because I can't cope with
more then 2 variables at the same time I am for 'simplicity' approch. The best 'definition' of this
approch is from O.Wilde:'I have the simplest tastes. I am
alwys satisfid with the best'. So I am still seaching.
Raul will you please bring (more) light to this issue?


Cheers