Guitar hero VS Rock Band

I find myself wanting one of the two games and wish to ask the great advice of the people in the world. These two games are similiar in many ways and its hard to decide which is better. I have looked at reviews for both the games and they both have some pretty good ideas that differ them from each other. The game that i would be looking towards is one a little bit more layed back. Im not gonna become one of those hard core players and beat expert mode without even looking. this would be like a family game were me and my brothers play in the spiritual harmony of brotherlyness. Please help...Right now i am leaning more towards Guitar Hero but I need the great people of the worlds help.