Band of Outsiders (1964)

First, a few words about the video transfer, since I haven't seen the BFI/Gaumont/Criterion blu-rays compared closely anywhere online.

The Criterion blu-ray is the best-looking disc. All three are from the same 2010 Gaumont restoration, but the Criterion has been further greyscaled to remove the greenish chroma issues inherent in Gaumont's master.

But more pressingly, while the vast majority of the film is more or less visually identical between the Criterion and BFI discs (the aforementioned pretty minor chroma issues aside), a 23-second segment occurring between 1:08:23.625 and 01:08:46.000 on the BFI blu-ray has been replaced on the Criterion blu-ray with video from another source. ...A better source.

Criterion → BFI

The sequence on the Gaumont blu-ray looks the same as what's on the BFI.

Audio:
The BFI and Gaumont blu-rays sound the same. The Criterion blu-ray has received additional noise reduction. ...The BFI and Gaumont tracks are already very muffled.

The Criterion DVD sounds considerably better than any of the BDs and it is obvious that it was transferred from the same analogue elements. Those elements don't sound particularly good, so the DVD still sounds pretty poor by any objective standards. The lack of heavy NR makes the distortion in the mix more apparent on the DVD, but it still sounds much more alive and detailed.

In the dance sequence, the sounds of Odile, Arthur, and Franz snapping their fingers have been pretty much wiped out on the blu-rays, whereas they're loud and clear on the DVD.