I love Absolute or Stoli Raspberry Vodka. It is on the expensive side
and I would love to make my own. If you throw some berries in vodka
and let it infuse, it really doesn't taste like theirs. Also, theirs
will keep forever and I have a feeling with real fruit essence in it
(even after berries are removed), it will spoil. Any thoughts?

I know with the citrus vodka, they use only the peel. I don't see how
you could do something similar with berries.