RF4.5 for the win... it's not perfect but it's easily the best of an imperfect bunch. As for if it's worth the money you have to decide for yourself but think about this... how much are you looking at spending on your first plane? If a few hours sim time can save that plane, is it worth it? It's not just your first plane it'll save either... you can practice that new manoeuvre on the sim over and over till you see it happen in your sleep before you risk later, more expensive planes with it.

Remember though that no pilot is perfect and even world championship winners still crash sometimes. Every plane you buy/build will have, written on the tail in invisible ink, the date it will crash.