Tonight I made two Manhattans and drank half of each. (I combined the unconsumed halves into a super-Manhattan and may have it later).
One was a straight rye Manhattan composed of half WT rye, half Overholt, and about 1/3rd red vermouth.
The second was made using one of my bourbon blends, while the whiskey base is very complex, essentially it is a bourbon Manhattan because my blends are mostly bourbon (the rest is JD, some straight rye and some Canadian whiskies).
It is interesting how they differ. The rye Manhattan is much drier than the other one even though I used the same amount of vermouth in each. The bourbon-blend one has a smoky richness derived from the bourbon palate. The rye one is more austere, spicy underneath and ends up with a sandalwood-like palate (I think it was Jake Parrott who used this simile for a Manhattan made with Pikesville rye and I can only agree).
I preferred I think the bourbon-blend one, both were very good but again quite different.
I should add I used Angostura in the bourbon-blend one and Collins Orange bitters in the other: maybe next time I'll make them the same way and reverse the use of the bitters. Or I'll use cherry in the rye one and omit it from the bourbon one.
In these two today I used no absinthe or anise-based drink, but I might add this next time.
This exercise reminds me (if I may say) how good my bourbon-blend Manhattans are. I have decided to bring some of my blends to Sampler upcoming and use them to make the Manhattans for the Friday night dinner. There is no reason to use an unblended bourbon even spiked with Lot 40: my blend-based ones offer something like 100 or more straight whiskeys combined, leavened only with some Canadian whisky which improves their texture and drinkability. They are better than any Manhattan made with one bourbon, IMHO.
This will be a mondo Manhattan.