There are lots of factors that determine a good midlayer. A good golf midlayer should provide both warmth and flexibility, allowing the golfer to move freely during their swing, without feeling restricted. It should also be breathable and moisture wicking to keep the golfer dry and comfortable during play. The fabric should be lightweight and durable, able to withstand the rigors of the game.
A good midlayer should also have a sleek and stylish design that complements the golfers overall look on the course. Finally it should fit well and provide a comfortable, non-restrictive fit that allows a full range of movement.