I own the Tureck edition of the Italian Concerto, and I highly recommend it to anyone who enjoys a peek into how a musician of Tureck's stature approaches learning and interpreting a work.
As your uploaded image of the first page Andante shows, this is clearly not an 'urtext work' in the commonly understood sense. Tureck writes that since there survives no 'original' of this work -- only later copies and editions -- a true urtext is unattainable. Thus, she has chosen to edit the work according to her understanding of the 'performance practices' of the period. Of course, her decisions have been scrutinized and criticized by other pianists and IMO justly so, in one particular case. No one would -- or should -- confuse this with urtext.
I would describe this edition as 'What and urtext edition of the Italian Concerto would look like, after having ten piano lessons on the piece with Roselyn Tureck (pencil in-hand)."
I'm a big fan of performance editions. Those by Earl Wild of selected works by Liszt, are particularly illuminating, in their clever use of hand distribution to better do justice to the music itself. I would put Tureck's contribution alongside this. Her choices of fingering are interesting, because they directly serve the articulation of the music.