I think I deserve some new ink (for my pens), but I can't decide what I would like. I'll be using it in my TWSBI Diamond 530 (1.1mm italic nib, colour Iris). In my ideal world I'd have something that matched the rainbow metal trim. Just not sure what to get.

#FountainPens

@RonniesaurusHex
Failing that I would go for a high sheen ink like Organic Studio's Nitrogen.
@Steveg58 @RonniesaurusHex I also vote for OS Nitrogen. A similar ink is Diamine Skull & Roses or Krishna Moonview (the older formula has superior sheen)