A 3/2/1 formula is a good start.

3 parts vodka to 2 parts guava to 1 part sour mix.

I would do 1 1/2 oz. vodka for that recipe and 1/2 oz. guava and 3 oz. sour mix and shake very well w/ ice.

How strong do you like your drinks?
I might do 2 Oz vodka, 1/2 Oz each lemon & lime juice, 3/4 Oz guava juice, 1 bar spoon simple syrup. shake and serve over ice in a tajin rimmed glass.

100% vodka and leave the rest out in the counter as conversation pieces.

Mostly vodka .4-.6 oz and 1/4 of the mango or guava, only dash of sour mix. Easy on sour mix as I don't know how it's made. Sour mix and mango/guava can be equal if not too sour/sweet.
Taste it. Don't make a drink too sweet. Gives such a headache.

Torchy's Tacos is coming to Virginia?

Sounds like you’ve had a few already, stick with what’s working 🍻

What would the ratios be for this drink?
What would the ratios be for this drink?
What would the ratios be for this drink?
Devil’s Juice cocktail
-Cirrus Jala-Pina infused vodka
-guava
-house sour mix
and a Tajin rim
It is shaken served with ice.

Any good store bought sour mix? The vodka is local.

Any modifications you'd try, like mango or pineapple juice?

Thanks & cheers.