What questions are important to ask yourself when considering a HT physician?

With graduate school finishing up, I think I'm going to take the plunge into getting HT done. I've been using minoxidil since the beginning of the year, and can't say it's done much - maybe slowed down hair loss, but hard to tell. Going to start on Propecia (hopefully) within the next 2-3 weeks and see how that goes.

However, more importantly, what are the variables one should consider when choosing a physician when going under the knife.