Though lots of folks in these forums have expressed a dislike of it, I like RB3's position wave notation. You get to recognize the hand positions represented by various shapes and movable chords look exactly the same except for their root number.
In any case it's not that hard to learn to use both.
I'd discourage any attempt to use an acoustic/electric to play the game, which I've attempted. The game amplifies what you're playing, changing it to sound like the guitar used in the song. If you're playing an acoustic you'll drown that out--you're better off using your Squier; there are a number of people who participate in this thread who do. I personally bought an in inexpensive Epiphone LP Special II, which I can recommend except that at 10 lbs it feels like a boulder hung around your neck. (My Squier weights around 7 lbs).