The ability to have multiple users working in one window, without having them lose their place when they log off or close out of another tab/window makes this software extremely useful for our organization! I wish there was more customization available beyond just changing colors & fonts but that's not really too big issue at all because it works so well as long you know what your doing wtih CSS styling (which we do).
We use spit fire primarily during planning phases - gathering requirements from clients / stakeholders etc., then creating rough plans using Gantts which are used by everyone involved throughout execution phase including subcontractors who also can see progress via gants charts while still being able to work independently if needed.