This is not part of the Whisky Advent Calendar - I just thought that since I have a sample of this (courtesy of @thecyclingyogi!), I might as well do a side-by-side review. I have a full unopened bottle as well (paired with an unopened 1979 DE).
All of Diageo's "Classic Malts" have a "Distiller's Edition" expression, where the whisky is double matured in a different type of fortified wine (for how long, I do not know). With regards to Lagavulin, it is always a Pedro Ximinez cask. I believe this one was bottled in 1999.
The colour is a deep copper, darker than the 16. On the nose, incredibly rich and fruity, with the peat flowing in the background. A hint of pulled pork. Rum raisin, rich sherry, balsamic vinegar, seaweed and loads of vanilla. A perfect balance between peat and sweet. Water accentuates the balsamic while bringing the peat a little more forward.
The palate is thick and chewy - this is a beautiful sherry cask. The peat is quite restrained (but it is there), behind blackberry, damp earth, musty bookshelves, wet leather and some tropical fruits. Fantastic, wonderful stuff. Luxurious, more so with a drop of water.
The finish is surprisingly gentle yet deep, smokier now, with cracked black pepper and some sea spray - and peat rumbling in the background. This is an improvement on what was already an incredible malt - I'm tasting them side-by-side and the DE is the clear victor between two winners. This distillery continues to surprise me - they seem to do no wrong. Some friends and I visited Lagavulin in May and took the Warehouse Tour, where we were poured some incredible (and generous!) drams right out of the cask (including a 31 year old) - highly recommended!