Generally, Amex Membership Rewards (MR) points are considered "better" because of their superior flexibility. While Avios are a specific "currency" tied to the British Airways/Iberia ecosystem, Amex MR points can be transferred to over 12 different airline partners, including Avios at a 1:1 ratio. This means that if you have Amex points, you effectively have Avios plus the option to transfer to Delta, Emirates, or Virgin Atlantic if a better deal arises. In 2026, having "convertible" points is highly valued because it protects you against devaluations in a single airline's program. However, if you are a frequent flyer with British Airways and utilize "Companion Vouchers," earning Avios directly through a co-branded BA Amex card might be more efficient for your specific travel patterns. Essentially, Amex points provide a "safety net" of choice, while Avios are a targeted tool for specific airline redemptions.