It's a cheap material, and it looks cheap, but everyone from Spiewak to Ralph Lauren Black Label is making these things and charging a premium for them. This is a slipperly slope that leads to satin tour jackets a la early-70s The Guess Who. On the other hand, from a strictly utilitarian standpoint, there's something to be said for outerwear that can survive being crammed into a suitcase. Our advice on this is to choose a jacket with some structure, and not a wrinkled mess. And get one for less than $150 or so—like an Armani Exchange blazer—because this is not an item with a lot of stylistic shelf life. The material may last forever, but the trend won't fare nearly as well.