Err...umm..that's a tough one I wish someone could give a good comprehensive answer But then again... you can't do better than your best, right? At least I like to think that if I know I've put everything I have to a project, it must be as good as it can be at that moment. If it's not good enough to get you a job, then there must be some room for learning more. Oh, well...this is just me blabbering. I would like to see some reference too...