I've got 2 machines that I use when I quilt. Bernina 930(7") and Husqvarna Viking Sapphire 875(10" throat). I've quilted queen size quilts with the Bernina, requires lots of stuffing the quilt out of the way, but it can be done. The Sapphire makes it easier, but it can be a fussy machine at times. I have a walking foot and darning foot for both machines. FMQ is easier when I use the "Machinger" gloves, I can grip the quilt better. I've been machine quilting for over 20 years and learned what works for me and what doesn't.
Sharon