Dr. Pepper and ice cream?   Ugggh!   Dr.Pepper may be good for removing paint, but as a base for an ice cream soda - please!!   Root Beer has the right properties for an ice cream soda - nice mellow base that blends well with the creamy ice cream. Coca Cola can be good, but it can be harsh and it clashes.

It is also impossible to get a proper egg cream outside of the NYC area. Egg Creams were born and raised in Brooklyn and they don't travel well!