Polymaker Dual Color Silk PLA Filament Green-Chrome, Coextrusion Shiny PLA 3D Printer Filament Dichromatic 1kg - Silk Filament 1.75 PLA 2 Colors, Dimensional Accuracy +/- (Jadeite)

The most engineering-minded consumer brand in this space. Polylite is their everyday PLA, PolyMax adds impact resistance, and PolyWood nails the timber look. They publish data sheets and actually explain what's in their formulations.