Different ads sell different products. A campaign that looks average overall can be the best seller of your highest-margin product.
The Products report shows sales, units, customers, revenue, new-customer and recurring revenue, refunds, profit and average order value per product or category. An order's revenue is split across its line items by price. Pick a channel to count each sale with the credit the selected model gives that channel. Buyers are also tagged with each product they bought, so you can filter any report to a product's buyers.