view inside single page depending on selection

Hi
I need to create a site for products
Many of them may will have the same content (let's call it "description A") and some other products may have another content (description B)
My idea is to pre-create the content in a custom type for each kind of description in one wysiwyg field
Later, when a product is created (using another custom type) assign what kind of description will this product show, A or B and show the single product view with the selected description.
It is like a view on the sigle product page depending on the choice of another custom type (like a drop down menu) Is it possible? how can I do it? have you done anything like this in your demo sites? so I can see it
it would be great because when 1 description changes it changes in all the products of that kind, otherwise I would have to go product by product and change it
thanks and regards
Gustavo