Investors interested in Financial Transaction Services stocks are likely familiar with Global Payments (GPN) and MasterCard (MA) . But which of these two stocks is more attractive to value investors? We'll need to take a closer look to find out. There are plenty of strategies for discovering value stocks, but we have found that pairing a strong Zacks Rank with an impressive grade in the Value category of our Style Scores system produces the best returns. The proven Zacks Rank puts an emphasis on earnings es ...