I've now done hours and hours of AB comparisons between my Technics SL-10 and SL-7 decks.
I’ve been using the same carts (Technics EPC-202c, Ortofon OM20, ADC PSX-40, Technics 310MC) same music, kit (see signature below), room etc and to my ears, there is no doubt about it; other than with the 310MC cart, the SL-7 is the better sounding deck. Not by a massive margin but definitely better.
Just a touch more open, more cohesive, even a quieter background. A bit of a surprise, but that is how I hear it.
With the 310 cart though, the tables are reversed a bit. I guess the SL-10 was built, primarily, to be optimised with the 310MC. As they are virtually unobtainium at sensible money, it seems a bit of a non selling point now.
The SL-1O looks nicer though.
End of mini review.