Fact is, Detlof, I have *literally* taken the words out of your mouth (or posts, as it were)! Unlike you, I never managed to reproduce those high frequencies with my 63s --due to insufficient amplification, as you have noted elsewhere.
Rogerwalk: if you buy Quads you now know who the specialist is!
To put the "flat-speakers" case bluntly, there's no musical comparison between the two, IMHO and having lived with Apogees (internal c/over, however) & Quads very many years ago. This said, I humbly submit that Divas are beautiful all-rounders, indeed, great speakers and, as you intimate, difficult to match -- more so to surpass!