I’ve been using Noodler’s inks in my fountain pens for at least six years. The basic Black is my favorite ink of all time, dries fast, and is utterly impervious to water or erasure once dried on paper. The Fox Red is also a favorite. Expensive, but very cheap in comparison to disposable ballpoints, and much better for the environment.
Though I am only a recent convert to the world of fountain pens, I have been really impressed with the Noodler’s Bulletproof Black Ink. When I first got started I tried a number of inks including some from Lamy and Parker only to find my writing would fade and wash away with the slightest hint of moisture. I decided I needed something more permanent.
My research paid off when I discovered Noodler’s Inks. Noodler’s ink is all made in the USA. I’ve been impressed with the amount of information they provide regarding the various qualities and properties of their ink. As far as their ink goes, it’s great. The black ink that I use isn’t as richly black as others, but it certainly holds up to the bulletproof claim when faced with the elements (water, sun, etc). In terms of ink flow, I have found the Noodler’s to be perfect for my needs (although the ink is only one half of the equation, the nib being the other). I use a fine nib, and have never had a problem. I will point out, though, that this is variable from ink to ink (and nib to nib) even from the same manufacturer.
Noodler’s Ink is sold in larger volumes (88 ml vs 50 ml, in most cases) but at a lower cost per unit volume when compared to other brands. The one bottle of Bulletproof Black I bought doesn’t look like it will be running out anytime soon in the next few years.
Finally, Noodler’s produces a range of specialty inks with different classifications including fluorescence, forgery resistance, and archival fade-resistance to name but a few. I highly recommend poking around their website to learn more.
[Noodler's Inks put together this really thorough PDF detailing the various properties of all their inks. It's worth a look. ]