I should begin by saying the NAB Visa Mini is a good card. The annual fee is very low ($24), you get 55 days interest free and the card comes with a cash back offer where you can earn up to $120 per year (at 0.5% of purchases), which more than negates the annual fee. The card also comes with some high-end features, such as purchase protection and emergency travel insurance.
The idea of a tiny card is also very original and I admire NAB’s innovation in thinking outside the box (no pun intended). However, innovation is only good if it makes sense and the NAB Visa Mini does not.
Originally I thought the NAB Visa Mini was designed to fit more easily into a tiny handbag; however I'm assured by my girlfriend that a normal-sized credit card fits without a problem. Actually, the smaller size is likely to be problematic if the card is kept in a purse because it will be difficult to get out of a normal card slot.
The impracticality does not end there. Credit cards have been a standard size since the mid-1950s and all the associated devices (ATMs, EFTPOS terminals etc) expect normal-sized cards. As such, the NAB Visa Mini won't work in an ATM, non-swipe machine or a manual card imprinter.
NAB foresaw this problem. They decided not to abandon the idea of a tiny credit card, but rather provide a second, normal-sized companion card for use in those devices.
As an example, let's say you're going out on a Saturday night and want to take your NAB Visa Mini in your tiny handbag. Want to get some cash out from an ATM? You can't. How about paying for a taxi? Sorry, taxis use non-swipe EFTPOS terminals. For most practical occasions, you will need to take along your normal sized companion card, which largely defeats the novelty of the Visa Mini.
Bottom line: If you can get past the impracticality of the NAB Visa Mini (and I have a sneaking suspicion that the card's target market will have no problem with that), the NAB Visa Mini is a really good card. Like most cards, you'll get the most value from it if you pay your balance in full each month and collect enough cash-back to negate the annual fee.