We were fortunate enough to have these two Bowmore expressions on hand, both acquired in separate duty-free transactions abroad. It was a foregone conclusion to taste them against each other. Note that you can currently find the 18 yo at the LCBO, but not the 17.
The spirits look about the same colour in both bottles, but of course, Bowmore isn't shy about using caramel to give their whiskies an almost reddish hue.
So, putting 18 in the glass...
Nose: Subtle with smoke and sherry notes. Ripe fruit, baking spices and a touch of cocoa.
Palate: Just a flash of peat, a medium mouthfeel, deep limey citrus and salt.
Finish: Black pepper, butterscotch and wet, musty earth.
Switching over to 17 now.
Nose: Bold with strong spices and orange peel. Peat smoke, salt and must with a measure more cocoa than the 18.
Palate: Peat punch in the face that mellows into toffee or maple syrup. Splash of water opens this up beautifully.
Finish: Musty but pleasant with the peat returning back over toffee.
Judgement: Given that we paid $100+ for the 18 and $80 for the 17, at bang for your buck alone, 17 is our clear winner. The 18 is a tad astringent and feels like it's out of step in forming a flavour battle between the peat and sherry. The 17 is more true to the Bowmore 12 year flagship and kicks you right in the ol' islay.