Nose: It bites your nostrils when undiluted. Very sharp and alcoholic. This one needs water! After some time, it opens up. Dry sherry, seaweed, briny seashore, marzipan, roasted hazelnuts, some wet cardboard, burnt driftwood. The nose is still kinda closed.Mouth: Prickles on the tongue. Sweet and sour, oranges, lemonpeel, soysauce, salted caramel, sweet popcorn, a rush of ultra-black peatsmoke coats my mouth, walnuts appear, cardboardy in the finish. Slightly odd. The salt stayed on my lips after I swallowed.Comments: I honestly don’t know why they named this one the “amazing” cask. It is a good one no doubt, but definetly not better than the other MoS in the flight. Too expensive for what it has to offer. /88

https://justadram.org/feasting-on-ardbeg-part-1/

I had the luck to taste this unique Ardbeg and can confirm what Markjedi1 writes above. Indeed another "Amazing Cask" by Malts of Scotland. 

When you hear Ardbeg from a Sherry cask, you have an idea, what you can expect and this Whisky will not disappoint you. My guess is, that this was a PX cask for maturing, cause of this oily sweetness and lots of fruits. Its absolutely well balanced between salt, sweetness, peat and all these fruits. 

Smell: peat hit, sea, iodine, citrus, plum seeds, red fruits, orangeade come out after a while
Taste: bonfire, pharmacy atmosphere, smoke, sweet peat, unripe plums and cherries,
Finish: peat-sea, pits
Score: 6.5

Nose: smoke, notes of chocolate, light notes of raisins / cheery
Taste: Complex, slightly sweet smoke. Noticeable notes of cherry
Rating 92 | 10 0. A very pleasant position. Pleasant, slightly sweet smoke. Generally, a position worth recommending!

Smoked meat, leather, tobacco, dried fruit are visible, salty, earthy smoke in the background more. Very complex, changes over time, citrus peel appears, alcohol hidden well. There is varnished oak, ash and sweet fruit at the long finish.

http://kaypingers-whiskyblog.de/frontend/fullarticle.php?id=238 Color: full gold
Nose: Very sweet and honey-rich malt penetrates the layer of ash, coal, lead, licorice, wet cardboard and dull, earthy aromas of autumn leaves. Add caramelized sugar, hints of sherry, some tobacco and then gray again, dark aromas.
Taste: Spicy with cayenne pepper, salt and chili as well as much peaty smoke. Fruity BBQ, dried fruits, beach campfire, mexican vegetables, lime and woody notes. Ash, charcoal, liquorice and gray clouds of smoke lead to a drier finish.
Finish: Medium long - dry-sweet, delicately fruity, but also dull gray. The peaty sweetness remains in the lead until the end
88 points (nose: 87 / taste: 89 / finish: 88)

Smell: salt, gum, cold smoke, grapefruit, anise, licorice

Taste: very alcoholic warm onset, smoke, anise and liquorice are present immediately, especially the anise note is very pronounced and intense. In the finish, the substance becomes more fruity, grapefruit and lemon, but also the aniseed notes, which are dominant throughout all phases.
With water, the whisky does not get better, the smoke comes to the fore and hides some other flavors, the balance is not right.

Verdict: the whisky has good facilities, an oily pleasant consistency in the mouth and well-balanced flavors in the full proof variety.
Overall, I am of the opinion that it is an average good Ardbeg this age, the generally very high rated grades over 90P, I can not understand, however, the price is in my opinion too high, there are of Cadenhead and DL Ardbegs same age which are equal or higher value and are traded cheaper.

Note: 84P

Ardbeg and sherry can lead to a very nice marriage. The previous Ardbeg from Geert and Thomas was a great example. In this case I have some trouble with the beefy parts of the nose, but overall it keeps growing in the nice direction. Allow it to breathe.