I think they are formulaic. After this one, I'll hold off on playing the others for a while. I think they would get old quickly if you played them one after another. The 5 pack has some of the earlier games in it.
http://www.amazon.com/exec/obidos/tg...XRIU2?v=glance
I got it at WalMart for $19.95. I saw the same price at Target.