Maubank (previously called the Mauritius Post Bank) is a bank that was created out of thin air from the carcass of the bankrupt British American Insurance. It is a bank doomed to fail, because the reason for its existence is not actual financial viability but political masquerading. The customer service is repeatedly a nightmare. If someone ever complained to you that Mauritius is a place of mediocrity, then Maubank is the place where you will get to experience this in the greatest amplitude. Also expect a difference of treatment between foreigners and locals, as Mauritians are legendary ass-kissers when it comes to foreigners (in part because of the legacy of colonialism and in part because of a national inferiority complex which is habitually misinterpreted as the supposed "warmth" and "friendliness" of Mauritians). The mediocrity is at all levels and in all aspects, so it would be futile to pin-point one thing in particular. Take a glorious shortcut and avoid this bank at all costs.
It was their staff that stood out for me. They were really helpful, polite, accommodating and competent professionals. It was nice working with them.