Just my nickel opinion. I also would have said Jack for a long time in regards to sour-mash....but I think it's world popularity and huge demand has somewhat worsened the process. It is now a very much mass produced whiskey. George Dickel has been beating Jack Daniels for me for awhile now, in Tullahoma it's still very much a slow process handcrafted affair. They're both old Tennessee Sourmash Whiskey's, and Lynchberg and Tullahoma are a stone throw away from each other... but Dickel just seems to have retained the traditional smokey flavor and process more. I don't know if they have changed the process at Jack or not, and if they did they wouldn't admit it, it just doesn't seem the same. I also have high hopes for the new "Chattanooga Whiskey" once they move in fully....but having done plenty of back to back comparisons among friends we agree George Dickel has taken the crown for the best traditional Tennessee Sour-Mash. I recommend the George Dickel number 12 in particular.
One aside about "single barrels" I'm sorry but this has always been to me more about snob appeal and a way to appeal to elitists, then any tradition on making good whiskey. Marketing wise for making money and charging more it's genius. However, carefully tasting your barrels, and mixing them to retain your signature flavor is NOT cheaper...it's how you keep quality control. The Single barrel shenanigans I'm convinced is more marketing then a recipe for good whiskey, most of the single barrels I have sampled tend to be a roll of the dice as to how good they are are, I'm much safer getting my money's worth with the traditional blend created by craftsman choosing the right barrels selectively. The snobs who like to brag at the cost of their liquor more then drinking it may disagree.....but I think it's hype.
I don't put all Whiskey's on the same page...sometimes you want a coke, and sometimes you want a Dr. pepper...whiskey shouldn't all be lumped together either...George Dickel #12 is my favorite Sour Mash....but I have other favorites too...
For Bourbon I would say my favorites are Booker's, Makers Mark, and Buffalo Trace just because it's a killer value for the money and not far from Maker's. On Booker's beware though those number are not a lie, this will kick you on your ***, it's 63%, also ignore what I said about single barrels above, in the case of Booker's all I can say is it must truly be their best barrels, maybe the one single barrel worthy of it's snobbery, I like Maker's Mark, because they set the standard, also they don't seem to have changed their methods despite demand, it's just good quality you can count on, but Buffalo Trace is so close, that I can not help but see it as a best value.
For Scotch, well I like sour mash so of course I like smoke...and the Peaty smokey flavor of Talisker wins for me hands down. Talisker and Rauch Bier make for my kinda drinking evening. Talisker is a excellent Scotch, and truth be told maybe my favorite of all Whiskey's but darned expensive..it's a special occasion drink for me. It is not made the same as any other scotch because it comes from the island of Skye, they traditionally didn't have a lot of coal, so they used the peat native to their island. Peat is basically hundreds or thousands of years of stacked seaweed dried out on land, they cut it out of ground and use for fuel, it gives off A LOT of smoke...and gives this Scotch a near Hickory flavor.
For the people who swear by Jack, all i can say is buy your self a bottle of George Dickel number 12, and test it back to back with ANY version of Jack. if you still prefer Jack you have not lost anything by the trial......so far I have converted many a Jack fan after they taste what a traditional handcrafted whiskey should taste like. Jack back in the day may have been on par or better, but not today. That Dickel is cheaper, is a great plus, I guess they don't have the same global marketing bill.