The nose on this is pure port with some brown sugar. The palate is similarly big on wine with fruity port or sherry. Digging deep, there is a caramel bourbon note underneath, but I can't say I would pick it out if I didn't know this was actually a bourbon. The port notes increase as it trails off into the finish where it's joined by some oak.
It's not often that I taste something that's totally unique. Tasting blind, there is no way I would guess this was bourbon. If I had to compare it to anything, I would say it tastes most similar to the Navazos Palazzi sherried brandy than anything else I've tasted.
Usually when I taste finished bourbons, I'm left with the feeling that the finishing was just a method to add some sweetness to an inferior product. This one is more akin to a sherried Scotch where the wine notes become an integral part of the whiskey.