Several other FPNners have said what ediamond just said.
Noodler's Swishmix inks, including Nile Ebony, do need "better" paper to prevent feathering and bleeding (carefully explained on the Swisher website, with helpful recommendations for brands and labels of paper, some inexpensive), while the Noodler's-own-label inks neither feather nor bleed on just about any paper, and I've tried them on many (shadowing can happen with some colors on really-loose-fiber papers).
Noodler's-own-label Black is not the blackest ink on the market, but that hasn't prompted me to get rid of my two bottles

. A wet-writing, fine-point pen (the only one of those I have is my Hero 329) makes N's Black look its best. The drier the pen, the more brown-gray becomes noticeable.
(Edit: the following sentences changed a bit after a look at Greg Clark's 2006
Sampler under residential fluorescent-coil-through-frosted-glass lighting. Since the
Sampler is hand-marked, and by swabs not by pens, different copies might have different results.)
From what I've read here on the FPN, and from what I see in the
Sampler,
Noodler's Swishmix Nile Ebony is the blackest
.In this
Sampler, the black inks from Aladine, Artist Line (Abraxas), Aurora, Calligrafico, Caran d'Ache, Conway Stewart, Fahrney, J. Herbin, Levenger, Panache/Hunt, Pelikan/Cross, Platignum, Platinum, Private Reserve/Bexley, Rotring, Sailor and Swisher's own label all seem to step about the same distance (but different directions) away from the unquestionable blackness of Noodler's Swishmix Nile Ebony.