ColumbiaMen's Glennaker Lake Packable Rain Jacket, Grill/Light Grey, Small

Is it made out of a breathable material?

Some say sizes run large; for cycling I don't like a floppy windbreaker. Any owners out there 5'10", 170#, 40" chest? I'm thinking Medium?

Is this a good warm(90°)weather jacket only for light rains?

How do you fold it up into a pouch like in the photo?