I know it's a pretty old topic, but I just wanted to let everyone know that with the forum's advice, I have also opened an American Express Blue Cash Preferred as of yesterday with a CL of 16,500 and APR of 12.99% after 15 months. I plan to use this card for all groceries, gas, and department store purchases, and default to the Visa Signature on all others.
Thank you all for the help! It will be saving me an approximate $500 per year or so! :-)