An attractive resume template/outline makes it more powerful. Just as dressing smartly helps a candidate in an interview good formatting does the same for a resume. Looks do matter at all places in the real world and on paper. When you present yourself well you get noticed. Similarly when you present a good resume it will be noticed; otherwise it would be very easily find a bin to rest in.
There used to be a day when you could create one generic resume and then blast it to a wide range of jobs you were interested in applying to. Even if you are using a resume service this practice of blasting is generally frowned upon. HR professionals are inundated with resumes and they want to see that applicants have read the ad and are responding directly to it. One-for-all type of resumes are easily spotted and are generally discounted by HR. So work with a resume service to see how you can best tailor yours for each job you are applying to.
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 cost is too good to be true. It is only human to try to find the best service at an affordable price. However it is also true that you get what you pay for. If a service says that it can write your resume for a few dollars it is better to be cautious. Creating good quality resumes requires using specific skills. The cost can be lower only if the summary of your career is part of a mass produced set of similar documents.
To distinguish the good resume writing services from the bad ones you need to find out how they proceed with the task. A good service asks you to fill out an online question. They also set you up for an interview with the writer. This ensures that the writer is aware of all details that must be present in your resume. If a personal interview is not possible they may also provide you with other ways to get in touch with the writer.