I already wrote about Tamdhu 12, as I got it from Advent Calendar last year, and I think it was great for its price. Now I got myself a taster of Tamdhu 12, 15 and 18. I still stand that Tamdhu 12 is great. But Tamdhu 15 is even better. Which is not always the case, mind you.
It is sweet, smooth, and leaves nice warmth not only in the throat, but also in the belly. With some liteheadiness on top.
Is it worth twice the price of Tamdhu 12? For the moment I think yes.