Mayo is an excellent choice, if you feel comfortable with the doctors there (this is always a very personal decision.) Is this where the clinical trial is being conducted? Who is sponsoring the clinical trial? I would ask the physicians conducting it about the quality of life issues that might be expected during and after the trial, knowing that they cannot always predict individual cases.
What other treatment options are being offered, and what would his prognosis be if he chose them? These are important issues to take into consideration.
Many patients with advanced cancer are eager to get into a clinical trial, if it is a protocol that may promise newer, more advanced approaches to treatment. I think that this is something that you should seriously consider, after exploring the issues I have mentioned as well as all your questions. Only you can make the decision as to what is right for you.
Sara Anne