I do think that this is an area of personal preference. I started FMQ on my domestic machine with a floating darning foot and did sort of OK. I purchased the hopping foot and did much better. I would just use what works best for you. As far as moving the quilt sandwich, the hopping foot does what its name says. It hops, in other words when the needle goes into the fabric, the foot hops down to hold it in place so the stitch can be made. When the stitch is completed, it hops back up. It takes some practice to quilt with the appropriate speed so you are in sync with the foot. Successful use of a hopping foot also may depend on a specific hopping foot setting on your machine. This setting also makes the feed dogs engage when the foot is down. They don't advance the fabric, they just apply pressure from the bottom to secure the fabric to make the stitch. Check your manual to see if your machine has a specific setting for this foot.