Mark, thanks so much for the comparison! And I'd never even head of mora.jp, so that's something to explore. When Quobuz bought eOnkyo, I knew the eOnkyo DSF catalog would be gutted.

I have purchased the new sacd edition and I have been able to compare it with the previous one from tower records, but also with the blu ray audio edition and the standard CD.

The CD was good with high dynamics and plenty of colours but I found the sound a little harsh sometime.
The tower records sacds are smoother but the dynamics are somewhat lost and the recording level is too low.

The blu ray audio edition is closer to the CD with less noise, sounding more digital, less analog but the harshness is not totally solved.

The new sacd edition definitely benefits from a new resmatering : it has everything you can expect, full range of dynamics but without harshness and the Wiener Philharmoniker play wonderfully.
At the end of her entrance, Mirella Freni's top note can be heard very easily, soaring above the orchestra the most beautifully while it was lost in the orchestra in all other previous versions.

That's why it surely is a new edition, probably the definitive one to possess although very pricey. I also find the packaging not very convenient as the sacds are not that easy to extract...

Thanks for the heads up Hade.

Detail matters, after all that's why we are devoted to SACD, so the refinements you refer to can be regarded as an improvement in SQ provided that it has not been enhanced (manipulated?) though some AI algorithm.

Alas, we have no way of knowing that unless our ears tell us of some aspect that sounds unnatural or artificial. Having planted that thought in your mind, it might then be worthwhile for you to listen again and see what you make of the enhanced details that you have noted.

There have been for sure some "manipulations" but call them parts of the remastering process. After all in the past, the final tape was made of several recording sessions, sometime with much more cuts & paste than one might think!
I had already noticed some manipulations by Decca specially since the remastering in 96kHz/24 bits :
. The Arabella with della Casa in the title role conducted by Solti sounded the oldest set in his complete recordings of Strauss' operas : the sound has been changed with the voices placed more forward and the orchestra with higher dynamics. The first issue (Decca Opera series) was not perfect but at least respected that era, the natural sound of the fifties, featuring the first recordings in stereo.
. The first Aida recorded by Karajan for Decca is another example : the same comment applies, plus Tebaldi's high note at the end of the Nile scene was corrected, sounding less flat!

Such changes were not necessary for the Butterfly set of course but the first sacds from tower records in their attempt to reduce the distortions really were a true disappointment (along with a Ballo in maschera under Muti... the only two old opera recordings issued by tower records on sacd so far sounding bad).

I am not against that kind of "manipulations" as long as the essential is preserved.
With that new Butterfly, it is the case indeed as I can only concentrate on the music without being disturbed. Enjoying Puccini's masterpiece is the most important after all, isn't it?
If there are some manipulations here, they are discrete and not exaggerated, the sound engineer must have been a musician or was trained as such by respecting the heritage he was given.
Like the La Bohême set, that Butterfly is unlikely to be issued in a standard case at more affordable price, it's a pity!

Excellent post Hade, thank you. John