*** Vodka is the most versatile because it has a neutral flavor. If you’re using vodka don’t worry about splurging for the expensive brands because it really doesn’t make a significant difference. Go for a cheaper brand – it’s the quality of the vanilla beans that counts.***
I made a lemon verbena liqueur using vodka last year. Darn good. My son the bartender and hobbiest chef told me the same thing about using cheap vodka, but I couldn’t do it because cheap vodka tastes like lighter fluid to me. So I opted for Grey Goose. I don’t know if it would have been better with cheap vodka, but the GG worked out nicely. Great for sipping or partnered with unsweet tea for a twist on Arnold Palmers.
I need to get busy and harvest my lemon verbena soon. It was delightful last year and it’s high time I start a new batch.
There is definitely a difference in the quality of vanilla beans & if you get ‘good’ ones, I can see where the vodka quality wouldn’t matter much, if at all. The vanilla definitely smells like vodka for a good while as the beans steep ... finally, you get that luscious vanilla smell, but it’s a bit of a wait.
One article I saw suggested making vanilla a year in advance ... always keep a steeping batch on hand. What I have now was started December a year ago. What I gifted last year, since I decided to do vanilla in November, was a nice bottle with beans/vodka in it & a tag as to when it would be ready (first available date - about 8 weeks) but also saying that the longer it steeps (like 6 months to a year), the better it will be.
For something like your lemon verbena liqueur, I would think the vodka quality ‘would’ matter more. Leaves vs beans ... the leaves wouldn’t be as intense I would think. Anyway, I’m glad it turned out for you! I grew lemon verbena many years ago in my herb garden and loved it (made tea out of it, if I remember correctly) .... might have to grow it next year (I have a spot) & try some liqueur. :-)