Software engineers frequently update COTS components integrated in component-based systems, and can often chose among many candidates produced by different vendors. This paper tackles both the problem of quickly identifying components that are syntactically compatible with the interface specifications, but badly integrate in target systems, and the problem of automatically generating regression test suites. The technique proposed in this paper to automatically generate compatibility and prioritized test suites is based on behavioral models that represent component interactions, and are automatically generated while executing the original test suites on previous versions of target systems.