I've been using the federal credit union at my university for about 7 years now, which was the time I spent in grad school. It worked perfectly with no complaints whatsoever; and since I was on campus all the time, I had no issues with the fact that the only ATM's belonging to the credit union were located on campus.
However, now I have graduated and have moved to a large city, where most of the ATMs I see belong to banks and are located behind locked doors accessible only to card-carrying members. I have all of my money in my credit union, and I do not currently care about earning interest or anything like that. Having used my student credit union basically for the last 7 years, I have no idea how any of this works. Should I just become a member at one of the big banks and close my credit union account?