When evaluating tungsten weights, the most critical factor is tungsten content, which should ideally be 95% to 97% to ensure maximum density and a smaller profile compared to lead. You must verify the insert-free design; high-quality weights are diamond-polished to ensure the center hole is smooth, preventing line fraying without the need for plastic inserts. Additionally, check the coating durability, such as electroplated or powder-coated finishes, which should resist chipping when bouncing off rocks or hard structures.