Yes, I've seen these conversion kits available for awhile now. It would seem as if it would make an ordinarily clunky cleaner even more cumbersome to use. He used to have another conversion kit where the bagless cyclone was mounted in the front of the handle, which seems like the best design, but IIRC, it cost about $200.00. It it had no filters to clog (and eventually have to be replaced) it might have more of a following.
I can only imagine how long that will take to get broken from the way it sticks out in front and back. Plus the way its built looks like only a slight bump and it would break. $200 could buy alot of Kirby bags...........