Sharepoint Best Pratice Analyzer

I have two questions;

1. Has anyone used the Sharepoint Best practices Analyzer If so, can you comment on it's value

2. When I try to use it I get an error. Error: (Network path cannot be found) I am using

sharepointbpa.exe -cmd analyzer -substitutions SERVER_NAME (the computer name of the server ) CentralAdminstrationServer (again the computer name of the server )

Thanks