I've heard some nasty stories about carbon bars, flat and risers. I have a friend who had a full carbon front end, dropped about 6 stairs, then went home. The next day, he wheeled his bike out of the garage and his bars cupcaked before he even got on. The scary thing about carbon is that it's hard to tell when it's broken.
I'm a flat-bar and bar-end man myself. I have some of those heavy aluminum bar ends (Avenir) that bend WAY over my hands. (Kinda like this, but moreso
http://cgi.ebay.com/New-Fuji-Mountai...QQcmdZViewItemI use them for climbing but i like em more for when i hit something with a bar. With risers and no ends, the tree catches the bar or my hand and throws me off, but with these ridiculous bar-ends, they just bounce off. Good luck, my man.