Original AMEX's foreign exchange rate is still lower compared to VISA even though the rebate is 1.5% only. I made 2 Japanese yen transactions and posted on same day 25/10/22, seen on 26/10/22.
The amount is 34930 yen.
AMEX post S$345.32, after rebate 1.5%, I pay $340.14. AMEX has 2.95% conversion fee.
StanChart SPREE post $353.45, after 3% rebate for online txns, I pay $342.85. SPREE has 3.5% conversion fee.
The exchange rate is lower for AMEX: 1 yen = S$0.00960277, before 2.95% conversion fee.
For VISA, 1 yen = S$0.0097766471, before 2.95% conversion fee.