You can keep both the Citi PM VISA and AMEX version.
BUT you cannot use the AMEX version at AXS machines to pay bills, that's where you need it for insurance premiums payment like Great Eastern Life.
Don't use this card for foreign transactions, I'm sure the admin fees are very high, just like UOB PRVI AMEX.
Note that miles cannot be transferred to Asia Miles!!
https://www.citibank.com.sg/gcb/cred...Code=SGCPMLNAV