Pilot Iroshizuku...every other fountain pen user besides me has used these before; do you have any favorite colors
I have a few, but I think that the only one that I've inked a pen up with thus far is the shading yellow-orange-red Iroshizuku Yu-Yake.
I like it---it's on a stub nib pen---but I haven't used similar yellow-orange-red inks from other ink manufacturers, like Noodler's Southwest Sunset, and I imagine that in practice, they're probably pretty similar to Pilot's ink.