I have to agree with G10. It depends on ones idea of "spinning". Personally, I use The Best Spinner, and heard someone earlier say it wasn't worth it. I would say that is only because they never took the time out to really learn how to properly use it.
That spinner is truly a time saver for me. Now, I NEVER put spun content on my own sites, and use them only for article distribution.
I am generally the author of the original article, which gets submitted somewhere like Ezine.. then that article spun and sent out to other, "less strict" article directories. Now, there are two options in that plugin... EVERYONES FAV & YOUR FAVs... I never use "Everyones Favs"...
I took an article that had MANY synonyms and went through that article word for word and saved each synonym to "My Favs".... this took nearly an hour and a half to really get it right... and I have heard some people spread it out over 3-5 articles to get their own favs set right.... but once they are set, the next article (and the rest from then on) are extremely quick and high quality, especially for a spinner. I have had much better quality article this way than I have some times when I outsource articles.
I guarantee that if you have never read the "original" copy article, and just ran across one of my spun articles, you wouldn't be able to tell.
Which, this goes back to G10's statement, it depends on ones definition of "spinning".