I just got one of these, black, from somewhere else and wow thats alot of ink. I know they say the amount but its still amazing to actually see it in person. Cant wait to see how good it really is.
For a good quality ink that is larger than the average bottle, we just launched the Noodler's Polar in 4.5 oz:
https://www.massdrop.com/buy/noodlers-polar-ink-4-5?s=noodler
They have a handy integrated eyedropper cap, and even come with a free fountain pen that's already set up for the eyedropper conversion.