Should I use Performance Max or Standard Shopping for ecommerce?

The 'PMax vs Standard Shopping' framing is misleading because the answer for most ecommerce accounts is 'both, with deliberate splits'. The question is which SKUs go where.

PMax is the right home for the bulk of the catalogue: broad reach, automated bidding, audience expansion. It is also where Google is investing most product development. Suppressing PMax entirely usually means leaving reach on the table.

Standard Shopping wins where control matters. High-margin hero SKUs where you want explicit bid control. SKUs that need to be defended at any cost (brand-defining lines). SKUs PMax keeps under-bidding because they convert slightly slower. New launches you want to bid up aggressively for two weeks. Anything where 'let the algorithm decide' is the wrong default.

The clean structure is: Standard Shopping campaigns ringfencing 10–20% of SKUs (the strategic ones), PMax handling the remaining 80–90% (the long-tail and the volume). Negative SKU IDs in PMax exclude what Standard Shopping owns. This stops PMax cannibalising Standard Shopping bidding and lets each do what it is good at.

Pure Standard Shopping accounts usually under-reach. Pure PMax accounts usually over-bid the wrong SKUs. The hybrid is harder to maintain but performs better on contribution profit in most catalogues we have seen.