Christopher Lee

Disney 4K Blu-ray is a mediocre upscale.

Hammer & Warner Archive 4K Blu-ray are confirmed by Randy Miller to be identical down to the encode, the only difference being different studio logos.

Warner Bros 2002 DVD has the best sounding mono

Caveat: mostly great video but the 4K Blu-rays have had additional DNR applied in some scenes on top of the DNR that had been applied in post-production and was already present on the DVDs & Blu-rays

The 2020 Blu-ray (the one without the green tint) may be better than the 4K Blu-ray?

New Line Blu-ray have the original 6.1 mixes

4K Blu-ray set is missing extras from the old Blu-ray/DVD releases

The 2011 Blu-ray notoriously had a green tint, the 2020 one removes it.

StudioCanal's 4K release is similar in encode quality, but has significant glitches in multiple frames. See comparisons 9-16 here: https://slow.pics/c/YkSVb3Ey

The pitch of the StudioCanal 4K's English audio is too high

Criterion has more extras than StudioCanal.

Disney 4K Blu-ray is a mediocre upscale.

Warner Bros 4K Blu-ray caps. Original 1.85 framing restored, much better colors, image detail and a film stock-like tone curve was restored.

Warner Bros HD-DVD has the original 6.1 mix in a better format than the Blu-ray (Dolby Digital Plus instead of standard Dolby Digital), but is still lossy and a disc prone to disc rot. The Blu-ray is a good alternative.