Life without opportunity for parole, if incarcerated in a facility where the individual actually LOST rights to all things society deems wonderful (TV, books, contact with outsiders, exercise facilities, etc.), then it MIGHT deter some from committing certain crimes. But we, as taxpayers, would still have to foot a hefty bill--especially as so many crimes these days could likely qualify for "life".
There are no "good" answers. Both long-term warehouseing of criminals and putting people to death are horrid options.
I suppose we could cryo-freeze them... then wake them up if/when we find a way to actually "rehabilitate" people.