Back story: the first time I had Booker's it was at a bar in Big Sky, Montana called "Whiskey Jack's". As a scotch drinker I asked what was on the top shelf. The bartender assured me that this was the best bottle in the bar.
If the measure of the "best bottle" is alcohol content, this is surely the best at 63% abv. But don't be scared off by that. This is a very good bourbon, just one with a lot of kick.
When you grab the glass, even before it reaches your nose, you'll see the dark, rich color and you'll smell the familiar sour mash smell and a closer inspection will reveal the high alcohol content. On the tongue, this is surprisingly smooth and strong, but will lots of sweet and spice notes. If you like to be warmed by a sip of something, this will do it and that warmth will linger after you've gulped this down along with some nice sweetness.