Funny enough, I get better customer service from Discover with their card then I get from Amex with my $500/year Platinum card. I've found my experience with Amex in general to have gone downhill over the last ~5 years or so.
I've found Amex's concierge to be okay and their travel product prices to be absurdly high. The only reason I keep my Platinum card is because I get $200 in Southwest gift cards each year with their airline reimbursement, and they reimburse me occasionally for my Global Entry membership renewal.