public static void PerfTest() { var wrap = new Wrap <SomeUnmockableObject>(new SomeUnmockableObject()); var sw = Stopwatch.StartNew(); for (var i = 0; i < 100000; i++) { var j = i; wrap.As <IUnmockable <SomeUnmockableObject> >() .Execute(m => m.Foo(j)); } sw.Elapsed.TotalSeconds.Should().BeLessThan(5); }