I do the same think with the AQS hoop. I attach it to the machine, put the quilt on top, align it with the heavy plastic template, put the magnets back on and off I go.
I bought the Quilt Topper and can't figure out how to use it accurately. How do you line up your design with out the gridded plastic template? I print a picture of my design and tape it to the template, and use that to align each section. I must be missing something because I can't figure out how to align the quilt with the Quilt Topper. It's just a big open square.