A first step to decide on the pin design is to see what works best for your niche by looking at existing pins and how they perform. If you find one design to be used predominantly, use that design.
If you find both designs being used in your niche, we would recommend you to try out both designs and see what performs best for your products.
You find more helpful tips in Lesson 4: Pinterest For eCommerce in Phase 6 of the Pinfluencer Academy curriculum.