Reserve raises the redemption value of all your Ultimate Rewards points to $0.015/point, but only if you use points purchase travel through the Chase portal.

Business Platinum has a feature which delivers about the same value $0.0155/point, but again only if you book through the American Express portal.

Both portals are outsourced, and there are service problems if flights are cancelled or changed.

Both programs have airline transfer partners in all three international airline alliances. with some overlap. Chase has more hotel partners.

There are threads in each forum with details of these features, please mention if you need links to something specific.

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