Ok so this was a rough experience for the simple fact that we were going to get our passports. DO NOT GO ON SATURDAY!! I repeat unless you have NO OTHER CHOICE don't do it! We made this mistake and then had to leave after finding out we had the wrong paperwork even after waiting for 3 hours (not exaggerating).
Definitely definitely make an appointment you will be first priority as an appointment and will be in and out in no time yet still make it for a weekday. This location given the crowd is extremely efficient and the supervisor there will take no ones crap she is on top of it! Be prepared to pry your mobile devices from your hands though as you will only be warned once about having them out after that you are asked (made) to leave. This place while not the most fun definitely gets the 4 stars for the ease and efficiency of the process.