I saw a video recently of a flybarless Hornet II. It appeared to be flying pretty well. It only had two blades, but there were no obvious problems with it.

I guess it's possible with model heli's.... Seems from what I read when googling flybarless isn't all that uncommon on models.

But it does seem to come with it's own issues that need to be understood when attempting it, as Vince suggested.

David