Precompiled headers are generally better for system/3rd-party headers. Module are better than PCHs for headers you own, although in some cases you may be better off not using them at all. (I say these because the benefit depends on the frequency with which you need to recompile them, and the relative coupling etc.) Depending on how heavy each one is in your codebase, and how often you modify global build settings, you may have a different experience. And neither is a substitute for keeping headers lightweight and decoupled.