What is it?
I tried a British NEW with the long teeth that was more aggressive than a common handle US NEW with short teeth, which in turn (for me at least) was more aggressive than a ball end old type.
Good shaves with all, I personally preferred the short tooth NEW.
I'm going to be trying this silver British NEW I came across very soon. Here it is compared to the American version. Note that it is slightly shorter in length and has a thicker base plate.
any old type pre 1920 IMO.