I've got Salsa Bell Laps on my bike, and I love them. The flare is actually a bit subtle. I don't know if it's enough to make a difference in leverage, but it gives a very natural feeling hand angle. I also like the "ergo" bend in the drops. The bump fits nicely in the palm of your hand. Other people don't like it because they feel like it limits hand positions, but I don't think so.
For a nice visual comparison of different flared bars, check out this post:
http://www.bikeforums.net/showthread...1#post12331287
I should also mention that I've got a pair of Salsa Pocos on a different bike. They're even more shallow than the Bell Laps with the same bend in the drops but without the flare.