I've used all the majors. Discover has by far the best customer service and account monitoring tools. If you want to talk to someone you can do so without going through a myriad of button-pressing menus, and the times I have talked to someone they have all been intelligent English speaking Americans.

I particularly like the tools that I can set up with my desktop or mobile app. A text or e-mail message can be sent whenever the card is used or at any particular $ level or above I chose, card is used outside the country, by phone or online, cash advance, or if the card has exceeded a certain amount. All these things are user settings. You can chose which ones you want and set your own criteria. Also you can shut off your card and turn it back on.

Cash back is 1% for everything no limit. Each quarter there are different 5% cash back categories. One quarter will be gas purchases, the next will be restaurants, then home improvement stores. Right now through the end of the year it's 5% at department stores and Amazon.

There's also Discover "Deals". If you use the Discover portal to get to an online seller there's 5-10% off and sometimes more from places like Best Buy, Walmart, Ace Hardware, Kmart, Home Depot, JC Penny, Sears, Walgreens, and tons more.

I use two other cards that fill the gap on cash discounts. Like my Amex Blue card I get 3% on groceries and 2% on gas. But Discover is the main card I use.