American Express Membership Rewards - Amex Blue Cash or Plat Cash Back (1.5% back)

I want a 1.5% cash back card with no limits.

Are there any sign up bonus for these cards?

Advise or Recommendations please?

I am not certain that the Platinum Cash Back card is still offered. I realize it is listed on the website, but there is no [Apply] button and typically this means the information is there for reference by existing cardholders.

If you'll consider Visa, and have a Fidelity account, the Fidelity Investment Rewards card gives you 1.5% cash back from the first dollar of spending, no limit.

http://personal.fidelity.com/products/checking/content/mcplatplus.shtml.cvsr