I bought a bottle of Brimstone last November, and it's still 2/3 full. It's not that I don't love it; it's a truly unique and distinctive dram. Like anchovies or vindaloo, I'm not often in the mood for it, but when I am, it's a craving.
The phrase "bold Balcones" is entirely redundant, and of the Balcones that I've tried, this is the boldest of the bold. It's smoke and barbeque sauce and some sage thrown in for good measure, with custard on the finish. What impresses me most is that it doesn't taste particularly young, even though it probably is, and there's certainly no ethanol harshness (particularly notable at 53% ABV) The working theory seems to be that the Texas climate dramatically accelerates the aging process.
This is a highly polarizing whiskey, but it absolutely works for me.