Different starting points
Nylon often gives a smooth, soft hand and is common in close-to-skin products. Polyester can offer a different balance of durability, moisture-management routes, colour behaviour and cost. The actual result depends on yarn, construction and finishing.
Choose by product requirement
Consider abrasion, colour, drying, hand feel, coverage, stretch recovery, pilling, care route and target cost together. A confirmed blend percentage should come from the production card or laboratory result, not from a product name.