Both translations are very much alike with the BFI just having the edge, same with the audio where the Criterion is just a little tinnier. But in terms of video the Criterion is definitely sharper and has less compression artefacts. The BFi disc loses some height, the Criterion is missing some width. The BFI has an introduction but the Criterion has a commentary.
I'd suggest getting the Criterion because the video is where there's the biggest difference and it's a lovely looking film.