Hi, yes we have. My advice is to gather all your documentation on what they agreed to do and what they have not done; a professional second opinion on what they've not done,and, if you don't feel you can argue your case well get someone else to do it for you.
We sued a builder in the SCC for not finishing cabinetry work and we lost. The SCC is more formal than we had expected. The builder had his barrister family friend to represent him and we felt like we were in the High Court! We were not at all prepared for that as had thought it would be informal and common sense would prevail. The Magistrate was like Judge Judy and really responded to the barrister while seemed to hate us - middle class lawyers, urghhh. It was extremely stressful, so factor that in also. Not trying to put you off but don't expect it to go your way even when you are in the right. Best of luck.