i have been investing in all of her templates. I love them, they make piecing so easy and there are lots of options available in her books, plus you can also use them for other patterns once you figure out which size you need.
The Kaleidoscope template makes a gorgeous little pattern; i'm making that one as my son's wedding quilt.
I have two daughter's that are also quilting, so i buy the templates and rulers and then we have a "lending library" set up where whomever needs a tool checks it out.