The last time we were there, it was about a 20 minute wait. But, it's fun watching others get their hair cut. While we waited I started talking to a very nice young man, who was all by himself. When I asked him if he was traveling solo, he said no, he wasn't traveling at all...he was a CM at WDW. That most of the guys really did get their hair cuts at the Main St. Barber Shop!!!
As far as the time they stop, they do close at 5. We have gotten there early in the morning, when they first open, and on a week-day. That works out the best for us. But, we aren't in a big rush to do the attractions so don't mind the wait, if there is one.