rulefan
Tour Winner
Polyester is not inherently waterproof. To make it so it will have a coating, possibly Teflon. However this is not 'breathable' so sweat will feel wet inside. Gore-Tex is probably the best know true waterproof.
However, there is a difference in technology and price between waterproof, water resistant, and water repellent.
However, there is a difference in technology and price between waterproof, water resistant, and water repellent.