Some random additions to this thread:

- Discover is accepted at all US Sam's Clubs, but you get only 0.25% cashback regardless of your annual spend.

- If you want to use Visa, MC, Discover with full cashback, or even AMEX for Sam's Club purchases: Go to any Wal-Mart; purchase a gift card using your chosen credit card; use the gift card @ Sam's Club.

- In the US, Visa & MC are accepted at the same level except where Visa pays big bucks for exclusive sponsorships, i.e. the olympics. Visa also is the "official card" of some attractions (Broadway, NFL) even though MC is widely accepted. Still in the US, MC is everywhere I want to be.

- Outside the US, Visa & MC are not nearly as ubiqutous. Especially in Europe, there are places where Visa is accepted but not MC.

- Most MC cards have better rental insurance than most Visa cards, but it can vary by issuer.



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On the road, In the air,
I enjoy travel, From here to there.