Are double doors more convenient?

We are long overdue to replace our front door. We have a wide stairway and area which could actually accommodate double doors, though we have a single door now. I love the way double doors look, especially the brown ones with the scroll work shown in the flash photos at this local contractor’s site. http://www.rwcnj.com/ourproducts/doors.htm

I figured out they are more expensive and wonder if, beyond how nice they look, are they practical and worth the investment? Do both doors open at once? This would probably make it easier to get in the doorway when you have packages from the grocery store and kids. I never lived in a home with double doors and was wondering if anyone else has them and whether they like them or not. Our current front door is in sad shape and I have to try to figure out a replacement now that the good weather it here.