I had viewed the Criterion extras but most probably would not return to them.
There are times I keep multiple editions but selling this one let me not feel too guilty about the double-dip .. especially since I had just splurged via dvdgo.com on the Spanish 10-disc Blu ray edition of the Jeremy Brett Complete Sherlock Holmes .. which my Oppo confirms is multi-region! A guilty pleasure ......
There's no guilt in loving the best Sherlock Holmes adaptation ever. I found those BD releases to be a bit spotty in the PQ department, though still quite a step up from the remastered DVD set from a few years back. Though they forgot to add the day-for-night filter on the boat chase scene in Sign of Four. Apart from that, though, great to have the series in 1080p.
As for M, I kept my Criterion release for the extras, but the Universum release is definitely the disc I pop in when I want to watch the film itself.