I made my first transfer using the FX service. I transferred CHF 150 to a Swiss bank account paying with a UK Visa debit card.

AmEx wanted £101.13* plus £10 = £111.13* (* IIRC as the promised e-mail confirmation hasn't arrived after about 45 minutes.)
Visa Europe's exchange rate for card transactions without card surcharge suggests £99.4167, @ 1.75% surcharge $101.1564
http://www.visaeurope.com/en/cardhol...nge_rates.aspx .

On this example, it looks as though AmEx charge a 1.75% FX fee on top of the service fee.

I presume I'll get 5,010 MRs including bonus for about £12. Not bad though I'm not sure the normal rate of 1MR/£10 is very attractive.