I have good harp space on my Janome Horizon and have successfully FMQ'd a number of queen sized quilts on it. That said, I have since done several in sections and really like it. I separately layered backing, batting & top sections for each quarter of the quilt (4 sections for straight set blocks), 3 for a quilt with blocks set on point. So much easier to quilt these smaller sections before joining them and works especially well on quilts without borders. It is a fun way to utilize pieced backings as well. Instructions for quilting in sections (also QAYG) can be found in many how to quilt books but I best understood it from one of Marti Michell's books about scrap quilting.