I very rarely achieve success in killing of MCs. I have never killed a viewpoint character, simply because it's messy. Almost all the time. (I won't go as far as saying ALL the time, but yeah, most.)
I once read a series of books where the MC--the POV character for the entire first book--died at the end of the book. I started the second book with the vague hope that (even though I'd seen his body) he might somehow make a come-back. It didn't happen. I was flabbergasted. Turns out, for the story, it worked. But I still felt cheated.
Killing off characters (to further the story) who are major but not central can be a very good thing. But killing off your POV often leaves the reader feeling cheated--as I felt. I can honestly say I've read few books where this worked out to my own satisfaction, or even felt right for the story.
Recently, I finished a series of books where the MC dies at the end of the four-novel story. But it was an act of self-sacrifice and one that (where you didn't see it coming) completely and utterly fulfilled the themes and character of the story itself. I didn't really want it to happen, but it felt right. It was good for the story.
But I think it's a really hard and risky thing to pull off.
I didn't like any part of that series much, so I suppose I'm not a valid source on whether it was a good move or not, though.... * grins *
