Heard too many reports of Ruger not returning the parts to take the chance. Especially if you have plans to reinstall the old parts. There are too many liability concerns and Ruger is usually unwilling to take a chance on it so it will be comlpetely at their discretion. That said, beyond the hammer and trigger, I don't know what all parts get replaced. I've never had it done, never will and never had to reinstall the old parts but I definitely recommend it.
You received some excellent advice from "flatgate" over on RugerForum. I would heed it, nobody knows more about Rugers than he.