I own DNS, but don't use it. I find I can type just as fast as I can generate ideas in my head. Plus I talk to myself a lot while typing, and that makes it difficult.
I like to use Power Article Rewriter, not to re-write by synonym, but it will spark a lot of ideas on how to change around an entire paragraph.
Takes me around 15ish minutes to re-write a 500 word topic, something either that is supposed to go up on AC or something the publisher can attach their product to. Like weight-loss, pets, SEO, celebreties, things of that nature that get re-written everyday. Never did anything real technical though. The times I took a shot at those they seemed a lot more trouble and time consuming than they were worth.