If you already have a controller, you can get the "upgrade" version of G-5 for $79.99 at Tower Hobbies. It does not require an old version to load up, it just requires you to be able to hook up a radio transmitter or one of their USB controllers.

I also have most of them, and as opjose, I prefer G5. I also have most, if not all, of their add-ons.

CGr.