Some of the best soda's are the housemade - all 3 flavors - at the chain BJ's Brewhouse.
Root Beer is the best soda, and A&W is one of the best despite being 'mass market'.
And Mug is a fine root beer.
One of the worst is Dad's and another is those cheap generic store brands.
There are too many good soads to list, but Pepsi > Coke, with the added benefit saying that pisses of the south.
And I've been to Coke headquarters, nice tour. At the end they sell a sampling of international products that includes absolutely disgusting sodas.
It's hard to see how anyone can drink the 'after dinner cleaning drink' for Italy.
Stewart's makes an excellent grape.
The best orange - and arguably the best mass market soda made - is Henry Wenhardt's Orange Cream, but only very cold.
For a special treat try to find the Limited Edition Virgil's Root Beer: