JPS,

You are right that the roof prisms are phase-coated to make the equivalent to the porro prisms, basically for contast. Roof prisms are more expensive due to have the prisms alined with each other in a straight line with the eyepiece. One advantage with the roof binoculars are that they are more compact than the Porro. This is sometimes need when bow hunting. Porro prisms are going to give you a great 3-D view.

Jon Jackoviak
The Optic Zone
www.theopticzone.com
[email protected]