AMEX has come on leaps and bounds in the UK in terms of who accepts it. A lot of merchants get it standard now when they apply for merchant accounts.

They regularly have promotions to attract small business. IIRC they now have a flat fee of 2.5% for small merchants, which isn't fair off the going rate for credit card fees.

I have a BA Amex but i don't use it as much as perhaps I ought to. I have a business platinum which I do the bulk purchases and just transfer the AMEX points to the private Avois