Have had this bottle for 4 years now.
I store all my whiskey exposed to no light, temperature stable in my heated/ AC home, and use a nitrogen argon barrier to prevent oxidation...point is little degradation would be my thought despite being open for so long.
This pour was slightly muted
Nothing negative
Nothing outstanding
Very drinkable/ enjoyable
Other than these Michters Toasted barrels have become so hard to get at retail I would probably not buy another, however would probably grab 1 if I had the opportunity to share with others as nice (NOT GREAT) bottle to have on hand, just north of $100 there are so many better bottles at or below that price point IMHO
Cheers