This was the most I've ever spent on a bottle, but I do feel I got this for a relatively decent price (about 190 USD). I'm a huge fan of the 12 and I LOVE the 18, which is what I'm getting at: I like the 18 far more than I did the 25. Despite the various flavors and HP profile I know and enjoy, for some reason the 25 was surprisingly harsh, and I regularly drink bourbons that are much higher proof than this 25yr HP. I've read here and there that some scotch doesn't 'do well' at higher proof and I think I understand now. Even my wife thought it basically burned going down, more so than even the standard wild turkey 101 that we both drink neat all the time.
I'll say again that I did like it; it was a delicious bottle and adding a touch of water seemed to smooth it out a bit but I guess I was expecting something more impressive than the HP18. And something smoother at a mere 101.4 proof. After finishing my first healthy pour, my throat felt dried out (like it does after sipping on George Stagg bourbon). I was briefly disappointed but quickly said f-it and poured another; I was celebrating after all.
Overall, I'm happy to have tried an old HP but will be content knowing I can treat myself to less expensive bottles and know I will love everything about it (the 18).
And a few nights ago I opened a Lag16 for the first time in a year and was reminded how perfect that whisky is.
cheers.

