It is depend to what you need.
People use third party service for clickbank because sometime it is hard to search and organize. I am personally don't like clickbank storefront site.
It is better for me to create micro niche site to target to promote one or specific clickbank product (cbengine have storefront to but I not using it). If you need to know what new product from specific categories, the gravity, earning etc ect, it is simple to use cbengine (just my opinion).
For more research about products and categories from different marketplace I use offervault.