Finally got a chance to use this as it's been surprisingly dry every time I got to ride to work this spring. I bought it for $19.99 from Iron Pony
http://www.ironpony.com/. I had put in a rather 'large' order and just threw this on as it seemed like a good idea.
It is basically a garbage bag in the shape of a suit. It was VERY dry last night I would expect it to stay this way unless it was somehow punctured. The main Zipper is very cheap and gets caught on folds too easily, however the fact that you can unzip right down to the knee is handy. In other words I'm glad I didn't pay more than 20 bucks for it, for 20 bucks it's a nice addition to my supply of bike gear.
Oh as for style...judging by the laugh the guys at work got out of it I'd say about 0