Twist to open “butterfly” double edge razors are not only convenient to use but they also have a place in cultural history: ask a random person on the street to describe an “old fashioned safety razor” and the odds are they’ll say something like ‘oh, that razor where the top doors opened up to change a blade with.’ With the right kind of razor blade storage magazine, blade changing can be a completely hands-off process.
The twist to open butterfly (AKA silo missile doors) double edge razor was the “state of the art” just prior to the introduction of cartridge razors. Since then that technology seems to have taken a back seat to less convenient, but easier to manufacture technology. But maybe we need to re-visit the TTO razor. Are there any good “modern” TTO razors? The linked article below delves into a few modern ones including the Viking’s Blade made in Australia.