I do not recommend just stopping by to have a chat. Program directors and students are extremely busy and visits to a program should be by invitation. You are basically asking the program to make a decision about your candidacy before they have even looked at your admission qualifications. Admission interviews take a lot of time and planning. If you have specific questions about a program, you could go to their web site, email the program director, or call to ask your questions. Stopping by without being invited is not in your best interests and you may not leave with a good impression if no one is able to take the time to show you around or answer your questions. Students may not be available either, they may be in class or off studying. So I suggest you do some research, and then fill out applications and wait to be invited for an interview. Good luck!! Etherbun