I stayed with Papa Carlo / Teatro Pace for four weeks. The flat looks exactly like the pictures and it is a great place to stay due to its proximity to Piazza Navona. Also, you can basically cover all key attractions/places of interest in Rome by walking.
Papa Carlo and his team are great - prior to arrival they already provided support and made recommendations regarding restaurants etc. During the stay they were always available in case of questions and they were extremely nice, helpful and supportive.