Casement windows maximize views and efficiency
Double hung windows may be charming, but those overlapping window sashes are smack dab in the middle of your view. Casement windows, on the other hand, are hinged at the side and let in the maximum amount of light and view whether open or closed. Winds that buffet your home actually push the window tightly against your house, rather than creating little vortexes between the upper and lower sashes as they do with double-hungs. Casements are a natural for ranch, contemporary, Southwestern and other architectural styles.
Casements are great for bedrooms, where they can open wide for emergency exiting and are easy to operate even for those who are wheelchair-bound. From the outside, however, the controls can be difficult to overcome for an intruder.
For wide windows use double casements, or install narrower casements for ventilation on each side of a large, fixed view window. It's easy to make a good case for casements.