Bowls definately conserve more weed and probably get you a little higher. This goes double for bongs. But with that being said, I prefer joints- with bowls, you have to clean them constantly to avoid the taste of spent resin, they clog up, and they usually look ridiculous. Joints are easy to roll, stay lit, and you don't have that ash/resin taste to the herb.
Really though, water bongs and waterfalls are better. Even blunts burn better than joints, if you have enough for one. The best smoking device is obviously a vapourizer, but the good ones are so damn expensive.
~Ethno