I picked one up at REI's last clearance sale and so far I like it. My size small came in under 10 ounces. The breathability panels are akin to stretch lycra. I haven't tried it out in a true rain shower, but I'm sure water will get in through the stretch panels. However, because of the panels, the jacket breathes amazingly well. A lil wetness might be worth the tradeoff for breathability. I dunno, I got mine for around town use (e.g. work, when im using an umbrella as well).
It's true, the jacket falls kind of funny. When its unzipped all the way, it kind of billows out like a cape. When its partially zipped up, the collar doesn't fall well, so its still stiff and upright.
But for a cheap price, its a good jacket