I was once given a bottle of Levenger Raven Black. It was really, really black, and quite featherocious. That property convinced me not to buy it again. It was probably quite a few years after it ran out before I bought the Borealis Black.
Before I tried Noodler's Black (or had even heard of it), I loved Levenger Raven Black, because it was SO black. Yes, it feathers, but back when I bought two large boxes of cartridges (international small), I guess the notebooks I was using were impervious to feathering. Or maybe I did notice and that was why I wanted to find the "best" black (according to my needs).
Currently, I'm using these cartridges in my Montblanc 100-Year Historical, because the pen is cartridge-only, and I'm remembering why I liked this ink as much as I did. As long as I don't use it on feather-prone paper. Sigh.