Despite being up and running for some eleven years, Kilchoman don't seem to have any plans for a standard ten year old release yet. I don't consider this necessarily a bad thing. Apart from the first few youthful bottlings, which I found as rough as an agricultural salt lick, I reckon that Kilchoman tastes very good at four or five or six years old.
The nose is sweet – banana cream with some salty earthy peat underneath., then the peat seems to get more floral. Iodically floral. Adding water makes it spirity, but also fresh and airy.
The palate is very, very sweet, soft, and drinkable. There's loads of earthy peat. It leaves a saltiness behind (or more precisely a salt-sweet note), plus a chili burn. With water it is still very sweet, light bodied, a little hotter than without water. The peat seems saltier – more sea air than earthy. Finish is now oddly drying. With time I'm starting to see some fruity notes, but the finish is definitely a bit rougher once water is added.
To conclude. A quarter cask expression seems like a good way to bring on maturing spirit more rapidly. I've always been a fan of the Laphroaig Quarter Cask, which is said to be about six years old, and I've tasted some delicious young octaves from Glenglassaugh. I like this expression a lot.