I have it and took a class last year. It is a great tool, but takes practice. I have always hand quilted. I still don't have the tecnique down yet, but it will definitely be worth it when I do.
Here is Jean Browns website. She is the main one that teaches it. Although she is retiring this year. But she has the tool, thimbles and hoops you need.
http://www.jeansimpressions.com/