Remember you resume will be read by humans as well as by machines which will scan for the right keywords. So put some time and energy into your keywords when you write. Resumes must grab the attention of both the human and the computer scanner.
No contact address is available. If the service does not have a physical location they may not be a suitable option for you. The chances are they are more into mass production of average documents. Numerous resume mills employ non-skilled individuals overseas to create these documents. They get hold of your current resume embellish it with the information available from the questionnaire and place it in a standard format.
The resume writing service does not require knowing anything about you. All they ask you to do is fill out a standard online questionnaire and maybe submit your current resume. A competent service needs you to fill out a questionnaire; however it does not end with this. They contact you and ask for numerous other details about your career and achievements that they need to create an effective resume.