dependency injection with MEF in MVC3 seems abnormally slow
===

I have an MVC3  web application where controllers use services to perform certain tasks.
I use to instantiate the needed services in each action separately,like so for example:

     public ActionResult Index()
        {
            ICustomService customService = new CustomService();
            var list = customService.ReturnSomething();
            .....
            return View(list)
        }
This was working fine. Then I decided to use MEF for dependecy injection in order to follow better design principles. So now I'm doing something like this:

    
       public class MyController : Controller
       {
        [Import]
        private ICustomService _customService;
        
        public MyController()
        {
            MEFManager.Compose(this);
        }
        
        public ActionResult Index()
        {
          var list = _customService.ReturnSomething();
          return View(list);
        }

     


Where Composition is done by MEFManage.Compose(this) which is the following function:

        public static void Compose(object o)
        {
            var container = new CompositionContainer(
                                                    new DirectoryCatalog(Path.Combine(
                                                                           AppDomain.CurrentDomain.BaseDirectory, "bin"))
                                                                        );
            var batch = new CompositionBatch();
            batch.AddPart(o);
            container.Compose(batch);
        }

This actually WORKS but it is  6 to 7 times slower than when I wasn't using MEF. 
Does anyone know why it is so slow? I am doing something wrong?
