Visa (V) is a stock to buy now because its one part of a duopoly.
Say all you want about Discover Financial (DFS) and American Express (AXP), but MasterCard (MA) and Visa own the vast majority of the credit card world and always will. Discover came along years ago and hasn’t done much to penetrate the outer walls of its competitors. And we always want to own companies that dominate their space.
I choose Visa over MasterCard only because, at the moment, Visa trades closer to its long-term growth rate. Valuation might not matter, but when all else is equal, why not go with the cheaper one?