I just stick to bleach based products for toilets!

I'd use Barkeeper's Friend for the same acidic effect without the sugar or brown color.

Sissyphus-

I hear you, and you may be correct in your conclusion, but I also know that acidic materials can have very different effects on two very similar materials. Coke bottles are made of glass and porcelain is made of other components. This is one of the explanations I found as to the difference between glass and porcelain: Glass is made by melting sand with a mixture of soda, potash and lime while porcelain is a hard, white, translucent ceramic that is made by firing kaolin and other materials.

Whether the two materials are equally impervious to phosphoric acid isn't clear to me.

Both are vitrified.....the components melted together in the kiln. Ever see any of those old marbles made from old toilets and sinks? That's what the porcelain looks like without the glaze that is put on top to make it glossy.

Coke won' hurt your toilet!

I second Barkeepers friend for toilets!