One of the best side benefits of being a business traveller has got to be the shopping.
Few globetrotters set off for an overseas trip without a shopping list either for themselves or usually for friends, family and work colleagues.
Australians can be excellent shoppers, especially once they escape the shackles of the relatively small and often overpriced local market.
The depressed state of the Aussie dollar resets the scale for the overseas shopper, however, making some duty-free purchases barely worth the trouble.
But where to buy, and what to buy? It varies from country to country, indeed airport to airport.
Top stops to shop
According to duty-free comparison website DutyFreeAddict, Hong Kong Airport has mid-range pricing for alcohol and electronics but tends to be on the high side for cosmetics, fragrances and fashion.
It's worth noting that Hong Kong has no general sales tax so in effect the entire city is one massive duty-free zone, although there's still a 40 per cent import duty on spirits.
Frequent flier Fiona Downes tells High Flyer that Heathrow remains one of her favourite airports to shop when it comes to sheer savings off the ticket price anywhere else in the world.
"I'm a bit of a collector of designer bags and I love spending time and money Heathrow's Terminal 3.
"The last bag I bought there, at T3's small Chanel boutique, I saved around a third off the retail price in Australia."
Sunglasses in general are much cheaper in the UK and US, Downes reflects, "while some high-end cosmetic brands – a good example is Giorgio Armani – don't sell their full range of foundation shades in Australia.
"I always stock up in the UK or US on items that we can't get here, and the price is usually at least equal but often better."
London's Heathrow Airport is one of the best places to grab a unique whisky duty-free, says Australian whiskey enthusiast and blogger Martin Eber.
"The dedicated World of Whiskies stores located in Terminals 2, 3, 4 and 5 offer whisky from all over the world, from a £10.50 ($22) Jack Daniels, to a £15,000 ($31,800) Dalmore Eos 59-year-old Scotch."
Eber singles out Japan as a little-known gem for lovers of the dram. "Low taxes and a nationwide thirst for rare and high-quality whiskies come together to make it a very appealing city for fans of whisky, or indeed any distilled spirit."
There's also been growth in the number of exclusive whiskies earmarked for sale only at airport duty-free stores.
"While some of these whiskies go for more marketing bling and style over substance, the vast majority of them are interesting, quality whiskies," Eber reflects.
"Take for example Craigellachie single malt from John Dewar & Sons. They sell 13, 17 and 23- year old expressions, but retain their 19 year old – with its bold, meaty character – solely for the duty-free market."
As a rule I'm happy to buy almost any gadget overseas if it runs off batteries – but I'm cautious of anything that has to plug straight into an AC wall socket.
Partly this comes down to the differences in AC voltage around the world and the issue of - or potential the lack of - international warranty, especially for larger, more expensive items.
Most consumer electronics gear uses a simple transformer that can handle anywhere from 110V to 240V and turns it into a much smaller DC voltage, so all you'll need will be an AC plug adaptor.
Singapore loses its shine
For decades Singapore traded on the notion of it being a haven for shoppers, especially breaking the journey en route from London or Europe in what was termed a 'shop-over'.
Those days are long gone, and it's questionable if Singapore is really that much cheaper on most significant items.
The debut of Australia's 10 per cent GST in 2000 replaced a raft of higher sales taxes which, in concert with a more mature import market and Singapore's own creeping GST (it's now at 7 per cent), narrowed the gap.
With the Singapore and Aussie dollars now almost at parity, there's often little advantage buying anything in the city-state compared to anywhere else.
That even extends to Australia: a pair of Bose QC20 noice-cancelling headphones costs $SGD466 or at Changi Airport, equivalent to $A455: that's more than $50 over their $A399 retail price in Australia (and around $365 duty-free at Aussie international airports).
That said, if you're flying with Singapore Airlines and making a stop-over at Changi, you can pick up $SGD40 ($38) in airport duty-free discount vouchers, which helps even out some pricing bumps.
Buying in the city
It can often be cheaper to buy something in the city instead of the airport.
Airports are duty-free zones but also have a captive audience, while city retailers will often discount below the cost of the GST.
There's typically a much larger range in city stores, too.
On an overseas trip last month I wanted to stock up on Terre D'Hermes, my favourite scent. But while my preference is for 50ml bottles, I found many airports only carried the largest 100ml bottle – and still at prices well above the likes of Sephora in Europe or the US.
Likewise, liquor in the US is generally cheaper at Walmart than duty-free at the airport.
When should you buy?
I've never seen sufficient justification for buying up on duty-free early in your journey and then having to cart those goodies halfway around the globe, unless you're gifting some bottles of the best Australian red wine.
(Mind you, this goes down a treat if you're visiting business contacts in Singapore, where the bill for wine can cost as much as an entire dinner.)
It makes more sense to set aside some shopping time on the last day of your trip and bundle the booty into your checked luggage, or pick up selected items at the airport before you head home.
Beware of booze
When you buy duty-free alcohol at the start of your long trip home with at least one stop-over airport on the way, be mindful that some airports won't allow your booze on board.
Singapore is a good example: the airport is set up so that the security check for liquids and gels takes place at the individual boarding gate for each flight instead of the entrance to the terminal.
As a result, that bottle of Dom Pérignon you bought at London Heathrow – which is definitely over the 100ml limit – will have to be binned at Changi Airport.
In the end, however, it can come down to a question of how much your time is worth.
Unless there are substantial savings to be had buying in the city compared to the airport – or even overseas compared to home – you can lose a lot of precious holiday time rushing around to compare prices.
What are your best tips for what to buy, and where to buy it, on your overseas trips? Let us know in the comments.
Few people spend more time on planes, in lounges or mulling over the best ways to use frequent flyer points than David Flynn, the editor of Australian Business tripler magazine. His unparalleled knowledge of all aspects of business travel connects strongly with the interests of 51698009 readers.