One is the single malt you would probably be able to buy in the supermarket, one is a slightly more expensive special edition of the same brand. The third, made at the same distillery in the 1970s, is from a bottle that would cost you hundreds were it ever to make it to the market.
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I have just had a tour of the Ardbeg distillery on Islay, and Jackie Thomson, our wonderfully knowledgeable guide, has been explaining exactly which taste notes to look out for in each of the peaty drams.
The question is, will I be able to tell the difference? Er, let's just say I won't be getting a job as a whisky taster any time soon. But then there are plenty who can tell the difference, as the abundance of malt aficionados from America, Japan, Scandinavia and Germany that I bump into on Islay shows.
For them, this island off the Kintyre peninsula is paradise and Islay's eight distilleries, which also include magical, romantic names such as Lagavulin, Laphroaig, Bunnahabhain, Bruichladdich and Caol Ila, are the holy grail of whisky.
Among them was a group of 10 young women visiting from Manhattan. The women, all in their 20s and 30s and impeccably dressed, meet monthly in New York to share their love of Scotch (never mind Sex And The City, for this group it's obviously Sex And The Whisky).
They certainly knew their stuff, and had been stocking up on special editions to take back to the US.
This trip, they said, was a pilgrimage, about as special as a holiday can get - like an opera-lover visiting La Scala in Milan, or a Shakespeare fan making it to Stratford-upon-Avon.
They were beguiled by the whisky, the history, the scenery, and they could not wait to tell their friends back in New York all about it.
It is surely this sort of free international publicity that will help keep Islay and its whisky thriving. But this island is much more than a drinkers' paradise. It is a paradise, too, for those who love birdwatching, walking, history and folklore, for those who want to eat beautiful seafood, and for those seeking simple tranquility. At various times of the year it is also a place to hear world-class jazz and traditional Scottish music, run a half-marathon, take part in a cycle race or go to a book festival.
The flight to Islay from Glasgow is itself a wonder. Only 30 minutes, it provides the most spectacular views of Scotland's west coast. The familiar 2D map of the coast is brought to life as you look out of the window and see the mainland break off into rugged coastlines, west and north to Ghia, Islay, Jura, Colonsay, Mull and beyond, over golden sands, aquamarine water and dark mountains. Perhaps the only others lucky enough to see such views are the tens of thousands of geese that come from Greenland to graze on Islay's rich grasses each winter.
The other thing you see as the plane comes in to land are the distilleries dotted along the south coast, each with its name emblazoned in big black Victorian letters, writ large and clear in the 19th century to help the puffer captains who would have sailed in to pick up the whisky.
My party of four is staying at the heart of one of these distilleries, Ardbeg, in the newly converted Seaview Cottage, which has all the mod cons expected by 21st-century holidaymakers - including the ubiquitous Smeg fridge.
It is fascinating to watch the distillery come to life early in the morning, as workers roll the barrels and prepare them for the long journey to mainland Scotland, Europe and beyond.
Standing in the garden on the shoreline, looking across to Kintyre, you can picture those puffers coming in, and seeing the old barrels stacked in the warehouse you get the feeling that little has changed since this distillery and others started production in the early 19th century. Ardbeg opened in 1815, the year Napoleon was defeated at Waterloo.
Ardbeg is well-placed for experiencing a whistlestop tour of Islay's other big draw, the scenery.
We start by heading north with our guide Christine Logan, an islander who not only knows every road, track and hill like the back of her hand, but brings the landscape alive with stories of the people and wildlife.
As if to highlight this shared existence, we stop off at Seal Bay to admire the grey seals relaxing on rocks and soaking up the August sunshine as curlews and herons look on.
From here it is on to visit Kildalton Cross, a monolithic Celtic cross in the churchyard of the ancient parish church, overlooking the hills. The cross itself dates from the eighth century, and inside the ruined church are the medieval carved tombs of warriors who fought occupiers during more tumultuous periods in the island's history.
Next it's on through the heart of the island from Port Ellen up towards Bowmore and Bridgend through the ancient peat bogs that give Islay's whisky its distinctive flavour.
The views are magnificent, transforming the hillsides and the bogs as the weather closes in and the sun fades to dark, threatening skies.
Sadly, we have no time on this overnight trip to head further north and cross over to Islay's wilder, more mountainous neighbour, Jura, or to travel west and experience the dramatic Atlantic coast around Portnahaven.
Those delights will have to wait for another visit. And there will be another visit, for although this island is indeed a whisky drinker's paradise, there is much more to it than that.