Sponsored Display Landing Destination (Product Page vs. Storefront)

Sponsored Display lets you choose where a click lands:

Product page — the recommended default.
Storefront — only worth choosing if the seller's store page is already proven to convert well; otherwise it adds a weaker step between click and purchase.

Rawlings also recommends advertising one product per Sponsored Display campaign for cleanliness, consistent with the general One-Product-Per-Campaign Structuring Principle principle.