Catsden..i have the sure foot which I am just now quilting my first quilt with. So far I love it as it has higher edges so you can't run over the rulers as I did when i quilted my last quilt. It was a constant battle with my last quilt without the sure foot as I had thicker batting and fleece as backing and no matter how hard i tried the ruler kept slipping into the needles path.
I asked around before i bought mine and everyone i asked said it was worth the money.
I have fleece backing on this quilt and not once have I had a ruler slip into the needles path. I definitely recommend it.