I've set up the Juki and started using it to quilt this gift piece. Right now I'm slowly stitching in the ditch around all the rectangles and will eventually fill in the cream background.
The Juki is performing very well. The mechanism is both stiffer and more solid than the Kenmore: it takes more effort to turn the hand wheel, but the whole machine is rock steady while running with the motor. The extra space through the harp is wonderful. I can rotate this whole lap quilt through it with ease. It seems to take more work to move the fabric under the embroidery foot, though, even with the presser foot pressure at the lowest setting.
However, that may be a function of my increasingly weak and painful shoulder. I have a rotator cuff injury in my right shoulder that is giving me fits. We've decided to spend a little more time here in Chattanooga so I can do some physical therapy. I don't think quilting is to blame for the injury, which hurts primarily when I lift my arm above shoulder height. While sewing doesn't hurt, it is tiring, so I'm dialing back how much I do each day to give my shoulder as much time and space as it needs to heal.