Run an explicit sensitivity review: reduce volume; reduce API prices hypothetically; increase human-review minutes; add required redundancy; and remove a planned discount. If the winner changes easily, buy a smaller experiment or shorter commitment. A robust no-build decision is often more valuable than an optimistic ranking.
The final comparison should contain measured results, assumptions, missing evidence and a next test for every viable option. This keeps supplier choice tied to the buyer’s problem instead of a fashionable training method.