The following video is part of our "Motley Fool Conversations" series, in which consumer goods editor and analyst Austin Smith discusses topics across the investing world.

In today's edition, Austin discusses four things investors eyeing American Express should keep on their radar. At the top of his list is an "opening" or relaxing of their closed-loop model. Being a closed-loop company has been a key in their success story up until now, but it has also curbed growth a bit. Watching how they manage a slightly more open model now that they have relationships with banks will be key going forward. Mobile payments, changing demographics, and its charge-off rate are three other key trends investors need to keep an eye on. At the end of the day, American Express remains a strong company with a great business model and robust management. The continued shift towards mobile payments should benefit them in the future, and that's just one reason Warren Buffett continues to own AmEx in his Berkshire Hathaway portfolio.

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Austin Smith has no positions in the stocks mentioned above. The Motley Fool owns shares of Bank of America, Berkshire Hathaway, and Citigroup. Motley Fool newsletter services recommend American Express Company, Berkshire Hathaway, and Visa. Try any of our Foolish newsletter services free for 30 days. We Fools may not all hold the same opinions, but we all believe that considering a diverse range of insights makes us better investors. The Motley Fool has a disclosure policy.