Thanks for the input, everyone. I went back and played with the machines today. For me, the deciding factor was the ease of moving the "pen" versus the "paper" for a larger sized quilt sandwich. For a wall-hanging or placemat sized quilt, moving the fabric around on the table (yes, with the surface designed for doing so) seemed just fine. The moment we switched to a throw sized quilt, it was a different story. The fabric was supported, but I felt much less able to manipulate it as I was quilting. I think I'll be going with a mid-arm (16") in a 5' frame.