There's already existing threads on this, please search a bit before creating a new one next time.
It's not better but useful for only 2 uses majorly:
1. Get the icici card discount in sale twice as it's applicable once on mc and once on amex.
2.Amex network offers
All above offers valid on 1st transaction by customer within 30 days of card set up(No minimum txn threshold) & are valid on both fee and non fee paying cards
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