This paper presents an experimental evaluation of our scenario-based multithreading for real-time object-oriented models by the use of a case study of a Private Branch eXchange (PBX) system. The PBX system was taken from the industry and exhibits a number of characteristics found in real-world applications such as a highly reconfigurable dynamic structure and a typical layered architecture. The objective of this experimental study is to assess the improvements to 1) the modeling environment in terms of ease of use for designers and 2) the performance of the resultant executables. We show how our toolset was applied to the PBX system to model scenarios, as well as to generate a scenario-based multithreaded executable. The study clearly shows that our method can handle large-scale, complex models and that scenariobased multithreading achieves the performance improvements for a real-world model.