Conklin Duragraph matte black with rose gold and Omniflex nib wasn't behaving. As per vendor's suggestion (Goulet), I reset the nib, and then heat set it. It now doesn't hard start or
Conklin® Mark Twain Crescent Filler™ Fountain Pen (Vintage Green with Gold Trim) - SwagXL
Skater Fountain Pen (Japan, 1950s-60s) - Black w Gold, Aerometric Fill, Extra-Fine Steel Nib (Excellent in Box, Works Well) - Peyton Street Pens