It might preserve identity from the perspective of the created copy, but the original still dies a death of disintegration the way I see it. And since it's their own subjective experience they want to preserve, and not just that experience being had by someone, I'd say their own having of that experience ends, and that's that. It's not that they die painlessly and wake up again, they die painlessly and something else wakes up, which they themselves will not be aware of, being dead and all that.
