Refactoring service-oriented software is crucial for competitiveness, security, and reliability. While the migration of monoliths to (micro-)services is well-studied, the evolution of a service-oriented architecture - particularly, the integration of API patterns - falls short, leaving practitioners with little knowledge on the impact of architectural refactorings. In this article, we employ an existing framework for applying refactorings either internally in the refactored service(s), adjacently (in the same application but another service component), or externally in a remote service. We study the impact on performance as observed on the client side of these implementation variants. Our work offers evidence-based guidance for building competitive service-oriented architectures upon evolution.