I have my Horizon on my quilting frame. My frame is an original Inspira frame. It has a 8" space between the rollers so I widened that by putting a steel 'repair' plate on where the takeup roller goes, then put the roller through the hole on the repair plate.
I use a Grace speed control - if you buy the one for the Janome 6600 it works.
The only drawback of using the Horizon on a frame is that the hood, the part that covers to the left side of the needle on the top is very big and can bump the front top bar. There really isn't anything inside that hood except the light for the needle, so I just took it off. I guess that makes me a radical. I would like to cover it up again just to keep the dust out, so I'm working on a plan to make a flatter cover out of plexiglass. If you have more questions, just PM me.