My friend has told me that American Express is the best out of 4 major credit card companies. I currently have 3 MC's, 2 Visas and 1 Discover. My scores are: EQ 734, EX 761 and TU 789. Would that help me bulid a better score if I get AMEX? I just received an application for a Blue Sky credit card and I'm thinking of filling it out.