scrivener is it any good?

I am reading The Secind Mouse Gets the Cheese by Carolyn Schriber and one of the programs she recommends to writers is scrivener.  I had never heard of it before so decided to take a look and see what I think of it.  I downloaded and installed a thirty day trial of it last night and am reading the tutorial.  They tell me it should take about two hours to go through it.  Once I get backtomy computer I will dig into it and see what I think.  My main concern is how well the spell checker works on it.  As a creative speller I really need a good spell checker and even then sometimes the one in Microsoft word throws up its hands in dispare and gives up one me.  Of course I will use my Dragon software which I hope will save me a lot of typing.  Stay tuned for more information as I experiment with both of these tools.