Raffles - thanks so much for the reply, that's exactly the info I was after. I think I'll take a look at the Lufty Amex (or the pure cashback one if I don't like the look of the other - it's just that simple old cashback seems a bit boring these days!)
I got the LloydsTSB 1,500 Airlimes sign-up last year and have done the AMS trip already with those miles (together with the one-night obligatory hotel stay, although that was a nice and cheap throwaway booking for £8 made in BKK!)