Isn't Death Being Too Merciful?

A jury recommended the death sentence for Scott Peterson today. I heard this on the radio as I was driving home. They mentioned how he had drowned his wife who was 8 months pregnant at the time. Her body, and then his unborn son's body washed up on the shore within a day of each other. Apparently, there really was no question about whether or not he did it- he did. What he committed is gruesome, cruel, cowardly... evil. I think I understand the almost visceral reaction that says he should be put to death. But, then I begin to wonder if he deserves the mercy that the death penalty presents to him. Isn't putting him to death, in some way, giving him the easy way out? I think that maybe he should have to spend the rest of his days locked up in a prison. Wouldn't he be punished more by having to live with the horror and shame of what he did? Also, I don't completely trust the state when they prosecute people. There have been too many people wrongly convicted and sentenced to die. It seems like life imprisonment is better for two reasons. One, the guilty actually suffer more for their crimes and two, in the event that the government has wrongly accused and convicted someone, life in prison isn't completely irreversible like the death penalty is.