Having bikes with drops, flats and Bosco bars, I'll throw my opinion in. For faster less take in the sights rides I get more power, better handling and have more fun on drops. For slower look around and smell the roses type rides nothing beats the comfort and versatility of the Bosco's. I commute 30mi round trip at least 3 days a week on drops and am fine. Went on a slow, pace with the wife, 20mi ride with drops last weekend and my neck was in agony from trying to look around and bs while we were riding. Flat bars just don't have enough hand positions for distance riding for me. I do find the Boscos to be a bit on the large side and have a cheap set of north road bars I'm kicking around trying. I'd really like to try a set of Civia Loring bars but they quit making them..


Image shamelessly ripped from this thread...

http://www.bikeforums.net/bicycle-me...-flat-bar.html