I should add that I drink a lot of my bourbons with ice... so I may be biased. But I also like a lot of them neat. But I think a few of them really improve with ice. KC1B is one.
weller_tex, I don't buy Bulleit often but I think it's great with ice, so it stands to reason that 4RSmB works. It's funny though, 4RSmB is one that I almost always drink neat.
I don't buy Bulleit Bourbon often, but buy the Rye quite a bit. Bulleit Bourbon is actually a dollar more than 4RSmB here so I just get it instead since I like the spiciness of 4R better..seems the Bulleit has more of the 4R juice floral notes to me.