Many To Many relationship with data in the association table

Hi all,

I am trying to make a bundle plugin with the possibility to add a quantity of products in the bundle.

Bundle 1:
Product 1 x X quantity
Product 2 x Y quantity

I have created a bundle table, an association table which contains the quantity field and extended the product entity.

When I am getting the bundle through the RepositoryFactory, I am getting the products attached but without the quantity field.

Any help most welcomed. If any more info needed just ask.

Thanks in advance