The cited product references establish the size/configuration questions, not which chair a particular person should buy. The Aeron reference presents three sizes, while the Leap reference lists adjustable lumbar support and arm options. Prices and individual comfort were not compared. Use the exact offered model rather than borrowing specifications from a different generation or configuration.
For a shared workspace, record both users and the adjustments each actually needs. For a single-user workspace, record desk constraints and return effort before narrowing the shortlist. A technically suitable chair can still be an unsuitable offer if delivery, assembly or the cost of returning it is unclear.
Make a short decision note: which configuration remains under consideration, what evidence is missing and what would eliminate the offer. Keep warranty and returns distinct; a support reference is not approval of a claim. Do not infer secondhand coverage from a current new-product headline.