Jerusalem Cafe falafel is just as good, the toppings bar is probably better, and you get a basket and utensils with your falafel, so it's easier to pile on the toppings with abandon. It's also not crowded and much larger.
However, it's also sort of weirdly depressing in there, with strange flourescent lighting, way too many tables, institutional atmosphere. This is a bigger factor than one might imagine, but I don't go as often due to this.