The dynamic nature of complex Cyber-Physical Systems (CPS) introduces new research challenges since they need to smartly deal with changing situations in their environment. This triggers the usage of methodologies that keep track of changes and raise alarms whether extra-functional requirements (e.g., safety, reliability, performance) are violated. In this context, we investigate the usage of formal methods as support to provide a model-based performance evaluation of smart CPS. The main goal is to understand to what extent well-known performance models, specifically Queueing Networks, are suitable to represent these dynamic scenarios.