Mine worked out decent but you have to be careful what they say they will cover. Mine covered a used transmission, not a rebuild of any sort. It also does not cover A/C work, flex fuel sensor and some other stuff.
I hear in Texas there is a class action lawsuit for these fly by night places that will sell you the warranty and deny the claim.
My suggestion is to research the company. Call a few shops and a couple dealers to see if they heard of them, then work with a shop that is experienced in dealing with these aftermarket warranty companies - they can usually give you the scoop before the work even begins.
B