The page summarizes the guarantee. The full terms are on the refund policy page.
When does the 60 days start: order, payment or delivery? Do opened bottles qualify? Must bottles be returned, and who pays shipping? How long does a refund take? Are there conditions on how much has been used? Do bonus guides affect anything?
The summary does not answer these, and the answers decide what the guarantee is worth.
Read it before you pay. Take a screenshot with the date. Compare each answer with what the home page says, and ask support in writing if the two differ. Keep your order email and the policy together in one folder.