I like to work with a combination of the two.
Coaching is a process where the coach entices the answers from the client. It is not their job to provide the answers, that is what consultants do. Coaching allows the individual to learn how to solve complex problems on his own.
Mentors are individuals who have been there done that. They give advice, on how they have done it in the past. A good coach will tell you when they switch from coach to mentor role.
As a coach, I prefer to work with industries that I have a limited amount of experience in. This way I am not "telling" my client how to do things. I am able to get them to solve their problem, this usually comes from inquisitive type questions that coaches ask.
An example I can use is with a current client. She owns a day spa, I have very limited experience in that industry, but she is having team issues. I have experience working with complex teams. I can ask her questions about her team, but coming from a totally different perspective. In this relationship, she has seen how she made some poor hiring choices, hiring people that do not share her core values. Now we are looking at changing hiring practices.
If you would like more info, please give me a call.