American Express shows how it's done

I just got a call from American Express. It came from a withheld number, so I didn't answer it. But I know it was American Express, because this is what happened afterwards:

1. they left a voicemail
2. the voicemail told me what it was about, gave me a number to call back, and referred explicitly to the fact they came from a withheld number: they were going to send a corresponding SMS to go some way to proving it was really them
3. they sent me a corresponding SMS
4. I called back the 01273 number (verifiable on the Amex website) they gave me

And then to the call itself. I was on hold for less than 15 seconds, didn't have to tell them what it was about ("Are you returning our call or is it about something else?"), and got a clear explanation for what happened with PayPal the other day. PayPal had decided -- without telling me while I was trying to make the payments -- to send through two transactions flagged as tests, because it was the first time my card was being used by them. This is apparently a trick scammers use, guessing card numbers and trying to open up access to them with test transactions. So, Amex just wondered if I'd tried to use PayPal and whether they could OK it.

American Express, you are awesome. Can you do current accounts? Savings accounts? Or contract your staff out to Tesco, NatWest, Nationwide, ... ?