Glowforge's Proofgrade materials are pre-tested with specific laser settings baked in — you scan the material, settings apply automatically, and you get predictable results without manual tuning. If you run a Glowforge and want reliable, dialed-in results without building your own settings library, Proofgrade is the path of least resistance. More expensive than raw sheet goods from other suppliers, but the time saved on test cuts has real value in a production context.