I just treated myself this afternoon with the Synapse BD.
I can't really talk about the PQ part of the release. It looks certainly very nice detail-wise, and the color-grading makes the movie pop in an incredible way. I'm used to screen-capturing the hell of Terrence Malick's movies BD releases because they just have so many gorgeous shots, but I could (and probably will) do the same here.
But the real treat for me was the AQ of the 4.0 mix. I'm used to audio restorations still sounding relatively dated. They often sound muffled, with a limited dynamic, dialogue lines sometimes can sound mumbled (even if they aren't !) and most of the time, high-frequencies have been filtered out. On top of that, many tracks are just mixed too low, and I have to increase a lot the volume of the receiver, which will also increase any background noise.
Here, it's just tremendous from start to finish. I originally wanted to push the sound a bit but ended up putting it back to the usual because it's already so energetic. The sound just fills the room on all adequate channels, with a very pleasing spatialisation and dynamic. It's not muffled, it feels very well mixed. While the PQ is "just" a competently done 4K restoration, the AQ seems even more worth the entry price because it's a rarer thing to get.
Like others however, I'm a tad disappointed by the extras (especially since I don't listen to audio com' anymore), including the booklet (though I liked the American Cinematographer reprint). I'm most especially surprised by the lack of any details on the restoration work. This is by far the longest restoration performed by Synapse, and Don May Jr has from time to time updated his blog with details about the findings on the element, the work on the restoration and the results. But while TLE has produced a 57 min extra on their restoration (included on the UK release), all Synapse offers is 3 pages about the sound restoration. It's very surprising but it also further make the whole package feeling too expensive. At a $60 price point, one expects a bit more. For instance, I'm very surprised that the Variety ITW of Argento hasn't been included here. It would seem logical : Variety is a US magazine (so same country as Synapse), it was made for the 40th anniversary / 4K resto of the movie, and it's included in the UK and the Australian releases.
On a unrelated note, the Synapse steelbook looks sold out at DVD Diabolik. However, Amazon now have some copies of it.