I think it would be interesting to compare Manhattans made the same way with three bourbons: one with Heaven Hill BIB 6 years old (or any comparable inexpensive bonded), one with a decently aged rye-recipe bourbon, say JBBL (or WT 101, or BT), and the last with a well-aged wheat recipe-bourbon, Pappy 15, say.
Ideally small adjustments should be made with water so the proof of the liquor is the same, otherwise a more alcoholic bourbon may seem more attractive than it should.
Make enough to combine the three for a fourth "vatted" Manhattan.
And then taste the four blindly.
Which would win?