There is also the option to spin capitalized words (assumed to be proper nouns) as well as leave any number of words unchanged, depending on whatever you enter into the "ignore" field, separated by commas. You also have the option to only keep the sentences that were altered a minimum percentage, as indicated by the "Keep Sentences that Changed" option.
I use Spinner Chief service, because it is able to rewrite content automatically, it doesn’t make load of mistakes that other spinners do, and it is much cheaper and it takes under 10 seconds to rewrite a 400–500 word article. And after reading the article you sometimes need a few minor edits which can be done on their spintax editor. I guess it is cheap because it is a new tool, but I took the advantage of it and get it for a low price. It is also nice because everyone can try it out for free.
It would really be ideal to have a content spinner where the result can be used on your primary blogs so if I’m lazy to write an article, I can just grab some articles somewhere then just spin it using my content spinner, but for me, the processed articles by Spin Rewriter is still not worthy to be published on primary blogs, but you can still try it if you want but make sure to read it meticulously and correct any grammatical errors.