I have mixed feelings about Diamine inks - I like the variety of colors and their intensity but many of them aren't well behaved (they tend to clog pens, cause nib creep / nib crud).
Ancient Copper has amazing color that I enjoy a lot but it causes terrible nib creep / nib crud. It's almost artistic in its expression:
Still, the color is great
Linum notebook - TWSBI 580, stub 1,1