Tmartinejn: you had probably read what Simonjtu had written elsewhere. :-)
Simontju: It's really inconceivable that the 9000es would sound more tonally accurate than the SCD-1 or 777; just by common sense. It'd be nice if you could describe specifically how you compared them. IME, memory is very bad at remembering subtle differences sound quality. So many times, I thought a tube is better from another of a different brand, only when listening to them for quite a while and swapping back, would I see that they aren't much difference. When describe subtle improvements, I think it's critical to do (and report) serious comparisions. You probably picked up the difference in dynamics quite easily, but the so-called "magic midrange" is a bit vague because it depends on many things: system synergy, musics, mood at the time you're listening.
ps: in terms of tweak, just by common sense, I'd like to think that Sony did really want their SACD products to do well, and probably put lots of efforts into them. Therefore, it makes more sense to me that "swap" tweaks would probably be better than "redesign" tweaks, which would mean that somehow we have a better understanding of the circuits than the engineers who created the products, and who work for a company at the magnitude of Sony