Please forgive me that I'm not using the prescribed format and did not compare to Oanda or Visa official rates. I recently traveled to Europe for 2 weeks and used quite a number of credit cards. When I compare the actual rate for the different cards on the same transaction date, this is the ranking I got:

In the order of best rates to worst rates:
1. Public Visa Infinite
2. HSBC Visa Signature
3. Maybank Visa Infinite
4. Citibank Premiermiles Visa Signature
5. Maybank Amex Reserve

The variance between 1. and 2. is almost 1% while 2&3 is very close to each other, 4. is rather close to 5