The Mormot Precip jacket I've been running for the last five years is one of the two best rain shells I've ever owned. It has FAR exceeded my expectations in every way. At a weight of 13 ounces and, thus far, impeccable waterproof performance with zero leaks, it's hard to imagine much better. The one place for theoretical improvement is in the noise of the fabric when moving, but if it's raining they can't hear that until their ears are ringing or their lungs are bleeding anyway.
