Huh. Well... I will not even try to morally justify myself: I would go through with it for the mere prospect of being able to watch the world from a point of view beyond that of a single life-span. That's my take on the answer: I would do it for my own, selfish reasons.
However, I don't see any real downside to any of this. As The7Sins mentioned, the "catch" isn't a catch at all: once you get past the moral justification, it becomes an inconvenience, and a minor one at that. Would you even care about one more life after watching billions succeed one another? If you are close to what resembles a god, immortal and powerful, why would you even keep any human values at all?
To top everything off, this is a "free" offer. Beyond the moral implications, there are absolutely no complications to discuss: you get what my fellow posters so aptly described as "pseudo-immortality", but you have absolutely no obligations to go through with anything what-so-ever because there is no "exit clause". You may stop whenever you want.
Whether you will be able to bring yourself to stop is another, in my opinion, much more interesting question, but it's entirely out of line here.
Now granted, it was interesting to see that the majority answered "Yes" in the poll.
It's a pity that the discussion per se was limited to a degree that there really wasn't much to get out of it; on eight pages of discussion, we mostly have: "Yes, and I will kill criminals!", "No, because it's not worth it" and the occasional deviant who misread the OP.
Also there is very little to no debate here. There hardly is any discussion going on; just people laying out their opinions about the OP and nobody actually trying to elevate the discussion any further than the original terms. In fact, many of the more "developed" responses do not account for any previous arguments or counter-arguments at all.
If we were debating, the natural consequence would be actually getting somewhere new by now.