I second this, but Discover is a very close second. I've been a very happy Amex user for better part of a decade now.
Only downside was their built in travel insurance didn’t cover me rebooking a flight because the first airline gave me a refund when they cancelled at 3am with me and my family staying in a hotel room across the street from the airport for a 6am airport arrival
Yes we got refunded but buying 4 tickets with a new airline the morning of our travel date cost me an additional $1800 over my refund. I guess there is no built in credit card insurance for that circumstance . (Screw you for leaving me stranded JetBlue!)