Your handlebars greatly effect the feel of your bike and how your bike handles. Sometimes bars that are comfortable for long rides aren’t the best for bike handling.
Mountain Bike Handlebars with a lot of back sweep (back sweep is how the handlebars point slightly back towards you, all mtb handlebars have some back sweep but most are between 3 and 9 degrees, these bars are 11 to 37 degrees) hurt your bike handling! I dislike them and they don’t like you! I have seen these handle bars recently on a few students bikes and they are scary and dangerous. I suppose if you have a nagging wrist injury or ride for more than 8 hours at a time they may be comfortable (but they are uncomfortable for me as my wrists have to twist outward to hold them) but comfort at the cost of greatly reduced control and risk of injury?! That doesn’t sound like a good trade off.
I got this photo from an interesting blog focused on bike as transportation and adventure (bike packing and long distance rides) check it out if you are into long rides:
http://www.pushingthepedals.com/2012/01/all-about-the-bend/ he likes the bars and for his purpose they are probably fine, he will be a little more twitchy but if they make him more comfortable that might make long rides more fun.
Have your ever ridden an old 3 speed with bars that bend straight back towards you? They are very twitchy. These new bars are similar. The more back sweep a bar has the more it moves your elbows in, towards your body. This puts you in an nonathletic position (elbows in) where you can not resist side to side bar movement nor can you move quickly or efficiently. This means when you hit a bump that causes the front wheel to swerve (which happens probably once a minute on a mountain bike) the input from the bars will be transferred to your body causing you to swerve. With a more straight bar and arms out from your side more you would; A. be able to resist the bars swerving and B. the movement of your arms would not be transferred to your body so the bump would not cause you to swerve. It is also hard to absorb shock and contour to the terrain as well with elbows in. So if your bike came with these bars switch them out asap! If you were thinking these type bars might be an upgrade, they are not! As we have stated before, look for a wide bar, 720mm to 810mm and a short stem, 30-70mm long and you will have much more control (assuming you understand and ride in proper body position).
Create you most in control ride yet!