Hi Henry, Yes, I can hear subtle differences among them, and yes, it is impossible or at least very difficult to sort out the root causes of those differences because of the tonearm/cartridge differences. However, I think those of us who regularly listen to a variety of different combinations can begin to discern what aspects of the sound are likely to be turntable-specific, especially if one keeps in mind that the major job of the turntable is to "keep time without a sense of effort". (I just invented that quote.)
In my case, I cannot easily run the same cartridge on all 4 turntables, because the "upstairs" system is geared to LOMC cartridges, and the basement system is MM/MI-dedicated. Despite all of this variance, I am very confident there is a kinship between the "sound" of the L07D and that of the TT101, and what those two have in common is a coreless motor. The Mk3 with Krebs mod has acquired a similar flavor but with even more "drive" (terribly inadequate word, sorry). Before the Krebs mod, I would say the Mk3 still had greatest drive but not as much continuity/liquidity/musicality to the sound.
I am very familiar with the two cartridges at play in my basement system (Grace Ruby with OCL stylus vs Acutex LPM320) running in my Lenco/Dynavector, so I can hear that the Acutex takes on a new dimension (I like it even better; it's rather shockingly good) running in the FR64S on the TT101. I intend to move the Grace over to the FR64S eventually, so I have a better bead on the Lenco vs TT101. The funny thing to me is that I was oblivious to MM and MI cartridges before Raul started his thread. Now he has gone back to MCs, and I cannot find a reason to spend big bucks on one of the high end MCs, even though I listen to two very good MCs upstairs.