I own two RT-909s and two RT-707s. Never owned any other RtR decks.
I bought my first 707 around 1980. IIRC, this was prior to - or near to - the invention of cassettes, so if you wanted to record, tape was the option.
Why do I keep them all these years? I bought all of my current decks before consumer ADCs were affordable and widely available. So again, if you wanted to record, tape was it.
And once you had the decks in those days it made sense to pick up some pre-recorded tapes. Theoretically less wear and tear vs. repeated plays of an LP, and the pioneers are fine sounding.
Anyway, that's my story about RtR.
Nowadays I record on a Sony or Korg to high res pcm or DSD...
I would sell the tape decks but the chances of shipping them without damage is basically nill.