I just ran across a post in another group about the Juki longarm. Apparently the Juki foot is ***not*** totally compatible with 1/4" thick rulers. Rulers work on 3 sides of the foot, but there is not enough space on the right side where the foot is attached to the presser bar. Plus, Juki made no provision for attaching a ruler table (necessary for when doing ruler work). Apparently Juki added a thread cutter because quilters were asking for one, but then failed to provide a means of doing the ruler work that most longarm owners expect to be able to do.
Now, this is all hearsay, but it would be well worth checking out before purchasing.