Continuous filament fibers minimize pilling and shedding, while cut-filament loop nylon may pill. Now it's more widely used for its durability and wool-like feel and appearance. Since it's dyed before it's made into a fiber, olefin is colorfast. However, some lower quality olefin can flatten and fade in direct sunlight. While it's not as durable as nylon, it's quite durable and resists wear.
Polyester offers a wide selection of textures and colors which it holds well.
It is non-allergenic, sheds moisture and resists moths and mildew at a lower cost than wool or nylon. While it's susceptible to pilling, shedding and oil-based stains, it otherwise cleans fairly easily and is enhanced by stain treatments. Acrylic the closest to wool of any of the synthetics. It's manufactured primarily for commercial use because of its springy feel, soil resistance, excellent cleanability and resistance to static, moths and mildew. It's available in a wide choice of colors, and is less likely to fade in bright sunlight than nylon or polyester.