The answer to your question is fairly complicated, but the best place to start is to ask yourself what kind of redemptions are you looking for? Perhaps the biggest benefit of Amex's MR points (and likewise Chase UR and SPG points) is the ability to transfer into different places as you need them. Each mileage program has it's strengths and weaknesses, so you need to think carefully about where you want to go first. For example short-haul tickets in coach (<650 miles) is best done via British Airways. Each one way ticket costs 4500 points, and several times a year Amex will give you a transfer bonus of 30-50%. Transcontinental business class tickets from LAX to JFK should be done through Singapore Airlines Krisflier program. A round-trip ticket will cost you 40k while most others will be 50k. The best value for flying from the East Coast to Europe in business is via ANA. That will set you back 68k for a round trip ticket compared to 90-100k with other airlines. Now back to the original question, where did you plan to go?
EX 798, EQ 789, TU 784
American Express Platinum (NPSL) || Bank of America Privileges with Travel Rewards Visa Signature - $23,200 CL
Barclays American Airlines Aviator Red World Elite Mastercard - $20,000 CL || Chase IHG Rewards World Mastercard - $25,000 CL
Chase Sapphire Preferred Visa Signature - $12,700 CL || Chase United MileagePlus Club World Elite MasterCard - $26,500 CL
Citibank Hilton Reserve Visa Signature - $20,000 CL || J.P. Morgan Ritz Carlton Visa Signature - $23,500 CL
