I'll go a little further. I've been using Noodler's inks, mostly Heart of Darkness (which is bulletproof), for several years. I started with a TWSBI but when I

I'll go a little further. I've been using Noodler's inks, mostly Heart of Darkness (which is bulletproof), for several years. I started with a TWSBI but when I upgraded to a Pilot Vanishing Point I continued to use Noodler's without any hesitation. It's continued to serve me well, and it remains my favorite and most dependable brand of ink. I did have one mold issue with Private Reserve in my TWSBI, and to be safe I have avoided using it in my Vanishing Point. I may be being overcautious though; I'm not sure how much to extrapolate from that one incident. My mother is an artist and has used several dozen Private Reserve inks spanning over a decade, all without any issues.