To me it was not worth, however is a personal opinion. You will need some info (i don't know what) from some one that i have real iPhone 4S then you will have to find a person that offer a Siri server that you can pay them to access the server.
I have a 4S and I don't use Siri much at all... I don't think is worth just to do a little dictation wish is what I use it for.
However somebody else will be able to help a little more. Keep in mind that is not legal to post links or information about Siri servers in here, so stay by the rules guys!