I find acceptance of Amex to vary depending where in the country that you are. In London there's anough choice around that you can find plenty of places that accept the card, smaller cities like southampton are a bit harder to find places that take amex.

Amex seem good when spending abroad, I always get a better rate spending on my amex in euros than I do with a visa or a master card.

My solution to this is to have both a Necter amex card and a Sainburys visa card. Sainsbury's visa card gives you some nectar points but not as many as the Nectar amex. I use the visa in the places that don't take amex. This means I get nectar points on nearly everything that I spend.

Best of all, as both the cards are free and I pay of the bills in full every month I pay no charges or interest, but each month I have enough nectar ponits to get money off shopping.