90%? I have had it work twice in 3 months...once at a dental office and once at a small Greek restaurant in Montreal. Never at a major retail or hotel chain.

I did call Amex about this. They blame the retailers. Apparently (they say) each retailer needs to do something to their card machine so that an Amex chip is accepted. The clerks just raise their eyebrows. Swiping after a chip refusal always works.

I'm getting tired of explaining the shortcomings of my new card. I use my Visa when I don't want the hassle.