Poire Prisoner - Pear In A Bottle

Hi Fruitheads
I grow pears in a bottle every year. See attached pictures, one European pear, one Asian pear. (Note: I will rotate the bottles so the water drains out sometime this week and reattach)
My problem is I have tried Eau De Vie, Rum, Brandy, Vodka in the bottle over the years, and none to my liking! Any ideas on what to fill em with?

pear in bottle 2


Grain alcohol.