I don't think you necessarily have to get it during O-Week. I got mine during the first week last year in one of the stalls near Donut King and the Commonwealth ATM. God I hate lines, I try to minimize cattle-ization when I'm in the city.
I might get one but tbh I don't think I'm going to be at uni enough this semester to put it to use. It's only good value if you're at uni a lot/live on campus and really involved in clubs and whatever IMO.